Updated logging plus more resilient coding to allow better run experience

.gitignore

@@ -24,6 +24,13 @@ _ReSharper*/
 [TestResult*/
 artifacts/
 publish/
+*.zip
+*.zip.txt
+*.zip.b64
+*.zip.b64.txt
+*.base64
+*.base64.txt
+*.certutil.txt
 
 HIP-VMs.txt
 hostcheck.ps

src/BizTalkMonitorConfigGenerator/BizTalk/BizTalkCatalogDiscoveryService.cs

@@ -9,12 +9,32 @@ using Microsoft.BizTalk.ExplorerOM;
 
 namespace BizTalkMonitorConfigGenerator.BizTalk
 {
+    /// <summary>
+    /// Discovers monitorable endpoints from the BizTalk management catalog.
+    /// </summary>
     public sealed class BizTalkCatalogDiscoveryService
     {
+        /// <summary>
+        /// BizTalk discovery options.
+        /// </summary>
         private readonly BizTalkOptions _options;
+
+        /// <summary>
+        /// Output defaults used while normalizing endpoints.
+        /// </summary>
         private readonly OutputOptions _outputOptions;
+
+        /// <summary>
+        /// Logger used for discovery decisions.
+        /// </summary>
         private readonly GeneratorFileLogger _logger;
 
+        /// <summary>
+        /// Initializes a new BizTalk catalog discovery service.
+        /// </summary>
+        /// <param name="options">BizTalk discovery options.</param>
+        /// <param name="outputOptions">Output defaults for generated targets.</param>
+        /// <param name="logger">Discovery logger.</param>
         public BizTalkCatalogDiscoveryService(BizTalkOptions options, OutputOptions outputOptions, GeneratorFileLogger logger)
         {
             _options = options ?? new BizTalkOptions();
@@ -22,10 +42,17 @@ namespace BizTalkMonitorConfigGenerator.BizTalk
             _logger = logger;
         }
 
+        /// <summary>
+        /// Discovers all configured BizTalk artifact endpoints and returns monitor-compatible endpoints.
+        /// </summary>
+        /// <returns>The discovered endpoints sorted by application, target name and endpoint.</returns>
         public IReadOnlyCollection<DiscoveredEndpoint> Discover()
         {
             var discovered = new List<DiscoveredEndpoint>();
+            var inspectedApplications = 0;
+            var skippedApplications = 0;
 
+            _logger.Info("BizTalk-Katalog wird geöffnet. IncludeSendPorts=" + _options.IncludeSendPorts + ", IncludeReceiveLocations=" + _options.IncludeReceiveLocations + ".");
             var catalog = new BtsCatalogExplorer();
             catalog.ConnectionString = _options.ConnectionString;
 
@@ -38,10 +65,14 @@ namespace BizTalkMonitorConfigGenerator.BizTalk
 
                 if (ShouldSkipApplication(application))
                 {
+                    skippedApplications++;
                     _logger.Info("BizTalk-Anwendung übersprungen: " + application.Name);
                     continue;
                 }
 
+                inspectedApplications++;
+                _logger.Info("BizTalk-Anwendung wird analysiert: " + application.Name);
+
                 if (_options.IncludeSendPorts)
                 {
                     DiscoverSendPorts(application, discovered);
@@ -53,6 +84,8 @@ namespace BizTalkMonitorConfigGenerator.BizTalk
                 }
             }
 
+            _logger.Info("BizTalk-Discovery beendet. AnalysierteAnwendungen=" + inspectedApplications + ", UebersprungeneAnwendungen=" + skippedApplications + ", UnterstuetzteTargets=" + discovered.Count + ".");
+
             return discovered
                 .OrderBy(x => x.MappedApplicationName, StringComparer.OrdinalIgnoreCase)
                 .ThenBy(x => x.TargetName, StringComparer.OrdinalIgnoreCase)
@@ -60,6 +93,11 @@ namespace BizTalkMonitorConfigGenerator.BizTalk
                 .ToList();
         }
 
+        /// <summary>
+        /// Discovers send port transports from one BizTalk application.
+        /// </summary>
+        /// <param name="application">The BizTalk application to inspect.</param>
+        /// <param name="discovered">The target collection receiving supported endpoints.</param>
         private void DiscoverSendPorts(Application application, List<DiscoveredEndpoint> discovered)
         {
             foreach (SendPort sendPort in application.SendPorts)
@@ -90,6 +128,11 @@ namespace BizTalkMonitorConfigGenerator.BizTalk
             }
         }
 
+        /// <summary>
+        /// Discovers receive locations from one BizTalk application.
+        /// </summary>
+        /// <param name="application">The BizTalk application to inspect.</param>
+        /// <param name="discovered">The target collection receiving supported endpoints.</param>
         private void DiscoverReceiveLocations(Application application, List<DiscoveredEndpoint> discovered)
         {
             foreach (ReceivePort receivePort in application.ReceivePorts)
@@ -131,6 +174,16 @@ namespace BizTalkMonitorConfigGenerator.BizTalk
             }
         }
 
+        /// <summary>
+        /// Adds a send port transport when it exists and can be normalized.
+        /// </summary>
+        /// <param name="discovered">The target collection receiving supported endpoints.</param>
+        /// <param name="bizTalkApplicationName">The source BizTalk application name.</param>
+        /// <param name="artifactType">The artifact type label.</param>
+        /// <param name="targetNameBase">The base name for the generated target.</param>
+        /// <param name="artifactName">The source artifact name.</param>
+        /// <param name="transport">The BizTalk transport information.</param>
+        /// <param name="isSecondary">True when the transport is a secondary send port transport.</param>
         private void AddTransportIfSupported(List<DiscoveredEndpoint> discovered, string bizTalkApplicationName, string artifactType, string targetNameBase, string artifactName, TransportInfo transport, bool isSecondary)
         {
             if (transport == null)
@@ -150,6 +203,17 @@ namespace BizTalkMonitorConfigGenerator.BizTalk
                 isSecondary);
         }
 
+        /// <summary>
+        /// Adds a discovered endpoint when artifact filters and endpoint normalization allow it.
+        /// </summary>
+        /// <param name="discovered">The target collection receiving supported endpoints.</param>
+        /// <param name="bizTalkApplicationName">The source BizTalk application name.</param>
+        /// <param name="artifactType">The artifact type label.</param>
+        /// <param name="targetNameBase">The base name for the generated target.</param>
+        /// <param name="artifactName">The source artifact name.</param>
+        /// <param name="adapterName">The BizTalk adapter name.</param>
+        /// <param name="sourceAddress">The raw address read from BizTalk.</param>
+        /// <param name="isSecondary">True when the endpoint is from a secondary transport.</param>
         private void AddEndpointIfSupported(List<DiscoveredEndpoint> discovered, string bizTalkApplicationName, string artifactType, string targetNameBase, string artifactName, string adapterName, string sourceAddress, bool isSecondary)
         {
             if (ShouldSkipArtifact(artifactName))
@@ -190,6 +254,11 @@ namespace BizTalkMonitorConfigGenerator.BizTalk
             _logger.Discovery("ADD", artifactType, bizTalkApplicationName, artifactName, adapterName, sourceAddress, normalizedEndpoint, "Zuordnung zu ApplicationName='" + mappedApplication + "'.");
         }
 
+        /// <summary>
+        /// Determines whether a BizTalk application should be skipped.
+        /// </summary>
+        /// <param name="application">The BizTalk application to inspect.</param>
+        /// <returns>True when the application should be skipped.</returns>
         private bool ShouldSkipApplication(Application application)
         {
             if (application == null)
@@ -205,6 +274,11 @@ namespace BizTalkMonitorConfigGenerator.BizTalk
             return _options.IgnoreApplications.Any(pattern => WildcardMatch(application.Name, pattern));
         }
 
+        /// <summary>
+        /// Determines whether a BizTalk artifact name matches a configured ignore pattern.
+        /// </summary>
+        /// <param name="artifactName">The artifact name to inspect.</param>
+        /// <returns>True when the artifact should be skipped.</returns>
         private bool ShouldSkipArtifact(string artifactName)
         {
             if (string.IsNullOrWhiteSpace(artifactName))
@@ -215,6 +289,13 @@ namespace BizTalkMonitorConfigGenerator.BizTalk
             return _options.IgnoreArtifactNamePatterns.Any(pattern => WildcardMatch(artifactName, pattern));
         }
 
+        /// <summary>
+        /// Resolves the generated monitor application name for a BizTalk artifact.
+        /// </summary>
+        /// <param name="bizTalkApplicationName">The source BizTalk application name.</param>
+        /// <param name="artifactType">The source artifact type.</param>
+        /// <param name="artifactName">The source artifact name.</param>
+        /// <returns>The generated monitor application name.</returns>
         private string ResolveMappedApplicationName(string bizTalkApplicationName, string artifactType, string artifactName)
         {
             foreach (var rule in _options.ArtifactMappings.Where(r => r != null && !string.IsNullOrWhiteSpace(r.ApplicationName)))
@@ -241,6 +322,14 @@ namespace BizTalkMonitorConfigGenerator.BizTalk
             return string.IsNullOrWhiteSpace(bizTalkApplicationName) ? "Unassigned Application" : bizTalkApplicationName.Trim();
         }
 
+        /// <summary>
+        /// Builds a generated monitor target name from BizTalk artifact metadata.
+        /// </summary>
+        /// <param name="artifactType">The source artifact type.</param>
+        /// <param name="baseName">The base artifact display name.</param>
+        /// <param name="adapterName">The BizTalk adapter name.</param>
+        /// <param name="isSecondary">True when the endpoint is from a secondary transport.</param>
+        /// <returns>The generated target name.</returns>
         private string BuildTargetName(string artifactType, string baseName, string adapterName, bool isSecondary)
         {
             var prefix = string.Equals(artifactType, "ReceiveLocation", StringComparison.OrdinalIgnoreCase)
@@ -261,6 +350,16 @@ namespace BizTalkMonitorConfigGenerator.BizTalk
             return name;
         }
 
+        /// <summary>
+        /// Normalizes a BizTalk adapter address into a monitor-compatible endpoint.
+        /// </summary>
+        /// <param name="sourceAddress">The raw address read from BizTalk.</param>
+        /// <param name="adapterName">The BizTalk adapter name.</param>
+        /// <param name="normalizedEndpoint">The normalized monitor endpoint when successful.</param>
+        /// <param name="port">The resolved explicit port when available.</param>
+        /// <param name="httpMethod">The generated HTTP method when applicable.</param>
+        /// <param name="reason">The skip reason when normalization fails.</param>
+        /// <returns>True when the address can be monitored; otherwise false.</returns>
         private bool TryNormalizeEndpoint(string sourceAddress, string adapterName, out string normalizedEndpoint, out int? port, out string httpMethod, out string reason)
         {
             normalizedEndpoint = string.Empty;
@@ -386,6 +485,11 @@ namespace BizTalkMonitorConfigGenerator.BizTalk
             return true;
         }
 
+        /// <summary>
+        /// Safely resolves the adapter name from a BizTalk transport.
+        /// </summary>
+        /// <param name="transport">The BizTalk transport information.</param>
+        /// <returns>The adapter name or an empty string.</returns>
         private static string ResolveAdapterName(TransportInfo transport)
         {
             try
@@ -398,6 +502,11 @@ namespace BizTalkMonitorConfigGenerator.BizTalk
             }
         }
 
+        /// <summary>
+        /// Safely resolves the adapter name from a BizTalk protocol type.
+        /// </summary>
+        /// <param name="transportType">The BizTalk protocol type.</param>
+        /// <returns>The adapter name or an empty string.</returns>
         private static string ResolveAdapterName(ProtocolType transportType)
         {
             try
@@ -410,6 +519,11 @@ namespace BizTalkMonitorConfigGenerator.BizTalk
             }
         }
 
+        /// <summary>
+        /// Safely reads the address from a BizTalk transport.
+        /// </summary>
+        /// <param name="transport">The BizTalk transport information.</param>
+        /// <returns>The transport address or an empty string.</returns>
         private static string SafeAddress(TransportInfo transport)
         {
             try
@@ -422,12 +536,23 @@ namespace BizTalkMonitorConfigGenerator.BizTalk
             }
         }
 
+        /// <summary>
+        /// Checks whether an adapter name contains a fragment.
+        /// </summary>
+        /// <param name="adapterName">The adapter name to inspect.</param>
+        /// <param name="fragment">The fragment to search for.</param>
+        /// <returns>True when the adapter name contains the fragment.</returns>
         private static bool AdapterContains(string adapterName, string fragment)
         {
             return !string.IsNullOrWhiteSpace(adapterName)
                    && adapterName.IndexOf(fragment, StringComparison.OrdinalIgnoreCase) >= 0;
         }
 
+        /// <summary>
+        /// Detects semicolon-separated email recipient lists that are not monitorable endpoints.
+        /// </summary>
+        /// <param name="value">The address value to inspect.</param>
+        /// <returns>True when the value looks like an email address list.</returns>
         private static bool LooksLikeEmailAddressList(string value)
         {
             if (string.IsNullOrWhiteSpace(value))
@@ -475,6 +600,12 @@ namespace BizTalkMonitorConfigGenerator.BizTalk
             return true;
         }
 
+        /// <summary>
+        /// Applies simple wildcard matching with asterisks and question marks.
+        /// </summary>
+        /// <param name="input">The input value.</param>
+        /// <param name="pattern">The wildcard pattern.</param>
+        /// <returns>True when the input matches the pattern.</returns>
         private static bool WildcardMatch(string input, string pattern)
         {
             if (string.IsNullOrWhiteSpace(pattern))
@@ -487,6 +618,11 @@ namespace BizTalkMonitorConfigGenerator.BizTalk
             return Regex.IsMatch(input, regex, RegexOptions.IgnoreCase | RegexOptions.CultureInvariant);
         }
 
+        /// <summary>
+        /// Determines whether a value looks like a host:port endpoint.
+        /// </summary>
+        /// <param name="value">The value to inspect.</param>
+        /// <returns>True when the value contains a host and numeric port.</returns>
         private static bool LooksLikeHostPort(string value)
         {
             if (string.IsNullOrWhiteSpace(value))
@@ -497,6 +633,11 @@ namespace BizTalkMonitorConfigGenerator.BizTalk
             return Regex.IsMatch(value.Trim(), @"^[a-zA-Z0-9._-]+:\d{1,5}($|/.*$)");
         }
 
+        /// <summary>
+        /// Parses a port from a host:port value.
+        /// </summary>
+        /// <param name="value">The value containing a port.</param>
+        /// <returns>The parsed port, or null when no port is found.</returns>
         private static int? ParsePort(string value)
         {
             if (string.IsNullOrWhiteSpace(value))

src/BizTalkMonitorConfigGenerator/BizTalk/DiscoveredEndpoint.cs

@@ -1,18 +1,68 @@
 namespace BizTalkMonitorConfigGenerator.BizTalk
 {
+    /// <summary>
+    /// Represents one BizTalk artifact endpoint that can be written as a monitor target.
+    /// </summary>
     public sealed class DiscoveredEndpoint
     {
+        /// <summary>
+        /// Gets or sets the BizTalk artifact type.
+        /// </summary>
         public string ArtifactType { get; set; }
+
+        /// <summary>
+        /// Gets or sets the source BizTalk application name.
+        /// </summary>
         public string BizTalkApplicationName { get; set; }
+
+        /// <summary>
+        /// Gets or sets the generated monitor application name.
+        /// </summary>
         public string MappedApplicationName { get; set; }
+
+        /// <summary>
+        /// Gets or sets the source BizTalk artifact name.
+        /// </summary>
         public string ArtifactName { get; set; }
+
+        /// <summary>
+        /// Gets or sets the BizTalk adapter name.
+        /// </summary>
         public string AdapterName { get; set; }
+
+        /// <summary>
+        /// Gets or sets the raw address read from BizTalk.
+        /// </summary>
         public string SourceAddress { get; set; }
+
+        /// <summary>
+        /// Gets or sets the monitor-compatible endpoint.
+        /// </summary>
         public string NormalizedEndpoint { get; set; }
+
+        /// <summary>
+        /// Gets or sets the generated monitor target name.
+        /// </summary>
         public string TargetName { get; set; }
+
+        /// <summary>
+        /// Gets or sets the HTTP method for generated HTTP targets.
+        /// </summary>
         public string HttpMethod { get; set; }
+
+        /// <summary>
+        /// Gets or sets the explicit target port, when resolved.
+        /// </summary>
         public int? Port { get; set; }
+
+        /// <summary>
+        /// Gets or sets an optional UNC path validation override.
+        /// </summary>
         public bool? ValidateUncPathAccess { get; set; }
+
+        /// <summary>
+        /// Gets or sets discovery detail text for diagnostics.
+        /// </summary>
         public string Detail { get; set; }
     }
 }

src/BizTalkMonitorConfigGenerator/Configuration/GeneratorConfiguration.cs

@@ -7,16 +7,51 @@ using HostAvailabilityMonitor.Configuration;
 
 namespace BizTalkMonitorConfigGenerator.Configuration
 {
+    /// <summary>
+    /// Root configuration for the BizTalk monitor configuration generator.
+    /// </summary>
     public sealed class GeneratorConfiguration
     {
+        /// <summary>
+        /// Gets or sets the generator name shown in logs and Event Log entries.
+        /// </summary>
         public string GeneratorName { get; set; } = "BizTalkMonitorConfigGenerator";
+
+        /// <summary>
+        /// Gets or sets the environment label used in logs and generated output.
+        /// </summary>
         public string EnvironmentName { get; set; } = "Unspecified Environment";
+
+        /// <summary>
+        /// Gets or sets rolling file log settings.
+        /// </summary>
         public GeneratorLoggingOptions Logging { get; set; } = new GeneratorLoggingOptions();
+
+        /// <summary>
+        /// Gets or sets Windows Event Log settings.
+        /// </summary>
         public GeneratorEventLogOptions EventLog { get; set; } = new GeneratorEventLogOptions();
+
+        /// <summary>
+        /// Gets or sets BizTalk discovery settings.
+        /// </summary>
         public BizTalkOptions BizTalk { get; set; } = new BizTalkOptions();
+
+        /// <summary>
+        /// Gets or sets output file and target defaults.
+        /// </summary>
         public OutputOptions Output { get; set; } = new OutputOptions();
+
+        /// <summary>
+        /// Gets or sets the monitor configuration template used for generated output.
+        /// </summary>
         public MonitorConfiguration GeneratedMonitorConfig { get; set; } = new MonitorConfiguration();
 
+        /// <summary>
+        /// Loads and normalizes generator configuration from a JSON file.
+        /// </summary>
+        /// <param name="path">The JSON configuration path.</param>
+        /// <returns>The normalized generator configuration.</returns>
         public static GeneratorConfiguration Load(string path)
         {
             if (!File.Exists(path))
@@ -74,6 +109,9 @@ namespace BizTalkMonitorConfigGenerator.Configuration
             return config;
         }
 
+        /// <summary>
+        /// Validates generator settings and applies safe defaults where possible.
+        /// </summary>
         public void Validate()
         {
             if (string.IsNullOrWhiteSpace(BizTalk.ConnectionString))
@@ -115,8 +153,16 @@ namespace BizTalkMonitorConfigGenerator.Configuration
         }
     }
 
+    /// <summary>
+    /// Provides recipient list normalization helpers shared by generator configuration validation.
+    /// </summary>
     internal static class RecipientListHelper
     {
+        /// <summary>
+        /// Removes null, empty and duplicate recipient entries.
+        /// </summary>
+        /// <param name="values">The recipient list from configuration.</param>
+        /// <returns>A normalized recipient list.</returns>
         internal static List<string> SanitizeRecipientList(List<string> values)
         {
             if (values == null)
@@ -131,6 +177,11 @@ namespace BizTalkMonitorConfigGenerator.Configuration
                 .ToList();
         }
 
+        /// <summary>
+        /// Counts all configured email recipients across To, Cc and Bcc.
+        /// </summary>
+        /// <param name="email">The email options to inspect.</param>
+        /// <returns>The number of configured recipients.</returns>
         internal static int GetConfiguredRecipientCount(EmailOptions email)
         {
             if (email == null)
@@ -144,65 +195,216 @@ namespace BizTalkMonitorConfigGenerator.Configuration
         }
     }
 
+    /// <summary>
+    /// Defines rolling file log settings for the generator.
+    /// </summary>
     public sealed class GeneratorLoggingOptions
     {
+        /// <summary>
+        /// Gets or sets the directory where generator log files are written.
+        /// </summary>
         public string LogDirectory { get; set; } = "logs";
+
+        /// <summary>
+        /// Gets or sets the daily generator log file prefix.
+        /// </summary>
         public string FilePrefix { get; set; } = "biztalk-monitor-config-generator";
+
+        /// <summary>
+        /// Gets or sets the number of daily generator log files to retain.
+        /// </summary>
         public int RetentionDays { get; set; } = 5;
     }
 
+    /// <summary>
+    /// Defines Windows Event Log behavior for the generator.
+    /// </summary>
     public sealed class GeneratorEventLogOptions
     {
+        /// <summary>
+        /// Gets or sets a value indicating whether Event Log writes are enabled.
+        /// </summary>
         public bool Enabled { get; set; } = true;
+
+        /// <summary>
+        /// Gets or sets the Windows Event Log name.
+        /// </summary>
         public string LogName { get; set; } = "Application";
+
+        /// <summary>
+        /// Gets or sets the Event Log source name.
+        /// </summary>
         public string Source { get; set; } = "BizTalkMonitorConfigGenerator";
+
+        /// <summary>
+        /// Gets or sets whether the generator should try to create the Event Log source.
+        /// </summary>
         public bool CreateSourceIfMissing { get; set; } = false;
+
+        /// <summary>
+        /// Gets or sets whether successful generator events should be written.
+        /// </summary>
         public bool WriteSuccessEntries { get; set; } = false;
+
+        /// <summary>
+        /// Gets or sets whether generator summary events should be written.
+        /// </summary>
         public bool WriteSummaryEntries { get; set; } = true;
     }
 
+    /// <summary>
+    /// Defines BizTalk artifact discovery behavior.
+    /// </summary>
     public sealed class BizTalkOptions
     {
+        /// <summary>
+        /// Gets or sets the BizTalk management database connection string.
+        /// </summary>
         public string ConnectionString { get; set; } = "SERVER=.;DATABASE=BizTalkMgmtDb;Integrated Security=SSPI";
+
+        /// <summary>
+        /// Gets or sets whether send ports should be discovered.
+        /// </summary>
         public bool IncludeSendPorts { get; set; } = true;
+
+        /// <summary>
+        /// Gets or sets whether receive locations should be discovered.
+        /// </summary>
         public bool IncludeReceiveLocations { get; set; } = true;
+
+        /// <summary>
+        /// Gets or sets whether only started send ports should be included.
+        /// </summary>
         public bool OnlyStartedSendPorts { get; set; } = true;
+
+        /// <summary>
+        /// Gets or sets whether only enabled receive locations should be included.
+        /// </summary>
         public bool OnlyEnabledReceiveLocations { get; set; } = true;
+
+        /// <summary>
+        /// Gets or sets whether secondary send port transports should be included.
+        /// </summary>
         public bool IncludeSecondaryTransportOnSendPorts { get; set; } = true;
+
+        /// <summary>
+        /// Gets or sets whether dynamic send ports should be included.
+        /// </summary>
         public bool IncludeDynamicSendPorts { get; set; } = false;
+
+        /// <summary>
+        /// Gets or sets whether local file paths should be emitted as monitor targets.
+        /// </summary>
         public bool IncludeLocalFilePaths { get; set; } = false;
+
+        /// <summary>
+        /// Gets or sets whether BizTalk system applications should be skipped.
+        /// </summary>
         public bool IgnoreSystemApplications { get; set; } = true;
+
+        /// <summary>
+        /// Gets or sets application name wildcard patterns to skip.
+        /// </summary>
         public List<string> IgnoreApplications { get; set; } = new List<string>();
+
+        /// <summary>
+        /// Gets or sets artifact name wildcard patterns to skip.
+        /// </summary>
         public List<string> IgnoreArtifactNamePatterns { get; set; } = new List<string>();
+
+        /// <summary>
+        /// Gets or sets application-level mapping rules for generated ApplicationName values.
+        /// </summary>
         public List<ApplicationMappingRule> ApplicationMappings { get; set; } = new List<ApplicationMappingRule>();
+
+        /// <summary>
+        /// Gets or sets artifact-level mapping rules for generated ApplicationName values.
+        /// </summary>
         public List<ArtifactMappingRule> ArtifactMappings { get; set; } = new List<ArtifactMappingRule>();
     }
 
+    /// <summary>
+    /// Defines output file behavior and defaults for generated monitor targets.
+    /// </summary>
     public sealed class OutputOptions
     {
+        /// <summary>
+        /// Gets or sets the generated monitor configuration output path.
+        /// </summary>
         public string Path { get; set; } = "generated-monitor-appsettings.json";
+
+        /// <summary>
+        /// Gets or sets whether an existing output file may be overwritten.
+        /// </summary>
         public bool OverwriteExisting { get; set; } = true;
+
+        /// <summary>
+        /// Gets or sets whether no discovered targets should produce a failing exit code.
+        /// </summary>
         public bool FailIfNoTargetsFound { get; set; } = false;
+
+        /// <summary>
+        /// Gets or sets the timeout assigned to generated targets.
+        /// </summary>
         public int TargetTimeoutSeconds { get; set; } = 10;
+
+        /// <summary>
+        /// Gets or sets whether generated targets are enabled by default.
+        /// </summary>
         public bool TargetEnabled { get; set; } = true;
+
+        /// <summary>
+        /// Gets or sets the HTTP method assigned to generated HTTP targets.
+        /// </summary>
         public string DefaultHttpMethod { get; set; } = "HEAD";
     }
 
+    /// <summary>
+    /// Maps a BizTalk application name pattern to a monitor application name.
+    /// </summary>
     public sealed class ApplicationMappingRule
     {
+        /// <summary>
+        /// Gets or sets the BizTalk application wildcard pattern.
+        /// </summary>
         public string BizTalkApplicationName { get; set; } = string.Empty;
+
+        /// <summary>
+        /// Gets or sets the generated monitor application name.
+        /// </summary>
         public string ApplicationName { get; set; } = string.Empty;
     }
 
+    /// <summary>
+    /// Maps a BizTalk artifact pattern to a monitor application name.
+    /// </summary>
     public sealed class ArtifactMappingRule
     {
+        /// <summary>
+        /// Gets or sets the optional BizTalk artifact type filter.
+        /// </summary>
         public string ArtifactType { get; set; } = string.Empty;
+
+        /// <summary>
+        /// Gets or sets the BizTalk artifact name wildcard pattern.
+        /// </summary>
         public string ArtifactNamePattern { get; set; } = string.Empty;
+
+        /// <summary>
+        /// Gets or sets the generated monitor application name.
+        /// </summary>
         public string ApplicationName { get; set; } = string.Empty;
     }
 
+    /// <summary>
+    /// Provides monitor configuration template helpers used by the generator.
+    /// </summary>
     internal static class MonitorConfigurationTemplateExtensions
     {
+        /// <summary>
+        /// Validates the monitor template without requiring generated targets.
+        /// </summary>
+        /// <param name="configuration">The monitor template to validate.</param>
         public static void ValidateTemplateWithoutTargets(this MonitorConfiguration configuration)
         {
             if (configuration == null)
@@ -274,6 +476,11 @@ namespace BizTalkMonitorConfigGenerator.Configuration
             }
         }
 
+        /// <summary>
+        /// Clones the monitor template while leaving the target list empty for generated output.
+        /// </summary>
+        /// <param name="configuration">The monitor template to clone.</param>
+        /// <returns>A monitor configuration clone without targets.</returns>
         public static MonitorConfiguration CloneWithoutTargets(this MonitorConfiguration configuration)
         {
             var clone = new MonitorConfiguration

src/BizTalkMonitorConfigGenerator/Logging/GeneratorEventLogger.cs

@@ -5,12 +5,31 @@ using BizTalkMonitorConfigGenerator.Configuration;
 
 namespace BizTalkMonitorConfigGenerator.Logging
 {
+    /// <summary>
+    /// Best-effort Windows Event Log writer for generator lifecycle and summary events.
+    /// </summary>
     public sealed class GeneratorEventLogger
     {
+        /// <summary>
+        /// Event Log settings from generator configuration.
+        /// </summary>
         private readonly GeneratorEventLogOptions _options;
+
+        /// <summary>
+        /// File logger used when Event Log writes fail.
+        /// </summary>
         private readonly GeneratorFileLogger _fallbackLogger;
+
+        /// <summary>
+        /// Indicates that Event Log writing has been disabled for this process.
+        /// </summary>
         private bool _disabled;
 
+        /// <summary>
+        /// Initializes a new generator Event Log writer.
+        /// </summary>
+        /// <param name="options">The Event Log configuration.</param>
+        /// <param name="fallbackLogger">The fallback file logger.</param>
         public GeneratorEventLogger(GeneratorEventLogOptions options, GeneratorFileLogger fallbackLogger)
         {
             _options = options ?? new GeneratorEventLogOptions();
@@ -18,6 +37,9 @@ namespace BizTalkMonitorConfigGenerator.Logging
             _disabled = !_options.Enabled;
         }
 
+        /// <summary>
+        /// Optionally creates the configured Event Log source.
+        /// </summary>
         public void TryInitialize()
         {
             if (_disabled || !_options.CreateSourceIfMissing)
@@ -43,11 +65,21 @@ namespace BizTalkMonitorConfigGenerator.Logging
             }
         }
 
+        /// <summary>
+        /// Writes an informational event.
+        /// </summary>
+        /// <param name="message">The event message.</param>
+        /// <param name="eventId">The event identifier.</param>
         public void Info(string message, int eventId)
         {
             Write(message, EventLogEntryType.Information, eventId, true);
         }
 
+        /// <summary>
+        /// Writes an informational event only when success entries are enabled.
+        /// </summary>
+        /// <param name="message">The event message.</param>
+        /// <param name="eventId">The event identifier.</param>
         public void InfoIfSuccessEnabled(string message, int eventId)
         {
             if (_options.WriteSuccessEntries)
@@ -56,16 +88,31 @@ namespace BizTalkMonitorConfigGenerator.Logging
             }
         }
 
+        /// <summary>
+        /// Writes a warning event.
+        /// </summary>
+        /// <param name="message">The event message.</param>
+        /// <param name="eventId">The event identifier.</param>
         public void Warning(string message, int eventId)
         {
             Write(message, EventLogEntryType.Warning, eventId, true);
         }
 
+        /// <summary>
+        /// Writes an error event.
+        /// </summary>
+        /// <param name="message">The event message.</param>
+        /// <param name="eventId">The event identifier.</param>
         public void Error(string message, int eventId)
         {
             Write(message, EventLogEntryType.Error, eventId, true);
         }
 
+        /// <summary>
+        /// Writes a generator summary event when summary entries are enabled.
+        /// </summary>
+        /// <param name="message">The summary message.</param>
+        /// <param name="hasWarnings">True when the summary should be written as a warning.</param>
         public void Summary(string message, bool hasWarnings)
         {
             if (!_options.WriteSummaryEntries)
@@ -76,6 +123,13 @@ namespace BizTalkMonitorConfigGenerator.Logging
             Write(message, hasWarnings ? EventLogEntryType.Warning : EventLogEntryType.Information, hasWarnings ? 2100 : 1100, true);
         }
 
+        /// <summary>
+        /// Writes one Event Log entry and disables future Event Log writes on failure.
+        /// </summary>
+        /// <param name="message">The event message.</param>
+        /// <param name="entryType">The Windows Event Log entry type.</param>
+        /// <param name="eventId">The event identifier.</param>
+        /// <param name="forceWrite">True to write the event when the logger is enabled.</param>
         private void Write(string message, EventLogEntryType entryType, int eventId, bool forceWrite)
         {
             if (_disabled || !forceWrite)
@@ -101,6 +155,10 @@ namespace BizTalkMonitorConfigGenerator.Logging
             }
         }
 
+        /// <summary>
+        /// Disables Event Log writes and records the reason in the fallback log.
+        /// </summary>
+        /// <param name="reason">The reason Event Log writes were disabled.</param>
         private void DisableAndFallback(string reason)
         {
             if (_disabled)

src/BizTalkMonitorConfigGenerator/Logging/GeneratorFileLogger.cs

@@ -5,15 +5,49 @@ using System.Threading;
 
 namespace BizTalkMonitorConfigGenerator.Logging
 {
+    /// <summary>
+    /// Writes rolling log files for BizTalk monitor configuration generation.
+    /// </summary>
     public sealed class GeneratorFileLogger
     {
+        /// <summary>
+        /// Synchronizes file writes within the current process.
+        /// </summary>
         private readonly object _sync = new object();
+
+        /// <summary>
+        /// Directory where generator logs are stored.
+        /// </summary>
         private readonly string _directory;
+
+        /// <summary>
+        /// Prefix used for daily generator log files.
+        /// </summary>
         private readonly string _filePrefix;
+
+        /// <summary>
+        /// Number of daily log files to retain.
+        /// </summary>
         private readonly int _retentionDays;
+
+        /// <summary>
+        /// Generator name written to log lines.
+        /// </summary>
         private readonly string _generatorName;
+
+        /// <summary>
+        /// Environment name written to log lines.
+        /// </summary>
         private readonly string _environmentName;
 
+        /// <summary>
+        /// Initializes a new generator file logger.
+        /// </summary>
+        /// <param name="directory">The target log directory.</param>
+        /// <param name="filePrefix">The daily log file prefix.</param>
+        /// <param name="retentionDays">The number of daily log files to retain.</param>
+        /// <param name="generatorName">The generator name written to log lines.</param>
+        /// <param name="environmentName">The environment name written to log lines.</param>
         public GeneratorFileLogger(string directory, string filePrefix, int retentionDays, string generatorName, string environmentName)
         {
             _directory = directory;
@@ -24,6 +58,9 @@ namespace BizTalkMonitorConfigGenerator.Logging
             Directory.CreateDirectory(_directory);
         }
 
+        /// <summary>
+        /// Deletes old rolling log files according to the retention setting.
+        /// </summary>
         public void CleanupOldFiles()
         {
             if (_retentionDays <= 0)
@@ -55,21 +92,44 @@ namespace BizTalkMonitorConfigGenerator.Logging
             }
         }
 
+        /// <summary>
+        /// Writes an informational log entry.
+        /// </summary>
+        /// <param name="message">The message to write.</param>
         public void Info(string message)
         {
             Write("INFO", message);
         }
 
+        /// <summary>
+        /// Writes a warning log entry.
+        /// </summary>
+        /// <param name="message">The message to write.</param>
         public void Warn(string message)
         {
             Write("WARN", message);
         }
 
+        /// <summary>
+        /// Writes an error log entry.
+        /// </summary>
+        /// <param name="message">The message to write.</param>
         public void Error(string message)
         {
             Write("ERROR", message);
         }
 
+        /// <summary>
+        /// Writes one structured discovery decision.
+        /// </summary>
+        /// <param name="action">The discovery action, such as ADD or SKIP.</param>
+        /// <param name="artifactType">The BizTalk artifact type.</param>
+        /// <param name="applicationName">The BizTalk application name.</param>
+        /// <param name="artifactName">The artifact name.</param>
+        /// <param name="adapterName">The adapter name.</param>
+        /// <param name="sourceAddress">The source address read from BizTalk.</param>
+        /// <param name="normalizedEndpoint">The generated monitor endpoint, if any.</param>
+        /// <param name="detail">The discovery detail or skip reason.</param>
         public void Discovery(string action, string artifactType, string applicationName, string artifactName, string adapterName, string sourceAddress, string normalizedEndpoint, string detail)
         {
             Write("DISCOVERY", string.Format(
@@ -85,6 +145,11 @@ namespace BizTalkMonitorConfigGenerator.Logging
                 Escape(detail)));
         }
 
+        /// <summary>
+        /// Formats and appends a generator log line.
+        /// </summary>
+        /// <param name="level">The log level text.</param>
+        /// <param name="message">The formatted message payload.</param>
         private void Write(string level, string message)
         {
             var line = string.Format(
@@ -104,6 +169,11 @@ namespace BizTalkMonitorConfigGenerator.Logging
             }
         }
 
+        /// <summary>
+        /// Appends a line to a file and retries transient file access failures.
+        /// </summary>
+        /// <param name="path">The log file path.</param>
+        /// <param name="line">The full line to append.</param>
         private void AppendWithRetries(string path, string line)
         {
             Exception lastException = null;
@@ -132,12 +202,22 @@ namespace BizTalkMonitorConfigGenerator.Logging
             }
         }
 
+        /// <summary>
+        /// Builds the daily generator log file path for the current local date.
+        /// </summary>
+        /// <returns>The current log file path.</returns>
         private string GetCurrentLogFilePath()
         {
             var fileName = _filePrefix + "-" + DateTime.Now.ToString("yyyy-MM-dd", CultureInfo.InvariantCulture) + ".log";
             return Path.Combine(_directory, fileName);
         }
 
+        /// <summary>
+        /// Extracts the date encoded in a rolling generator log file name.
+        /// </summary>
+        /// <param name="path">The log file path to inspect.</param>
+        /// <param name="date">The parsed file date when parsing succeeds.</param>
+        /// <returns>True when the date could be parsed; otherwise false.</returns>
         private bool TryGetDateFromFileName(string path, out DateTime date)
         {
             date = DateTime.MinValue;
@@ -156,6 +236,11 @@ namespace BizTalkMonitorConfigGenerator.Logging
                 out date);
         }
 
+        /// <summary>
+        /// Removes line breaks from values before they are written to one-line logs.
+        /// </summary>
+        /// <param name="value">The value to escape.</param>
+        /// <returns>The log-safe value.</returns>
         private static string Escape(string value)
         {
             return (value ?? string.Empty).Replace("\r", " ").Replace("\n", " ");

src/BizTalkMonitorConfigGenerator/Program.cs

@@ -10,48 +10,71 @@ using HostAvailabilityMonitor.Configuration;
 
 namespace BizTalkMonitorConfigGenerator
 {
+    /// <summary>
+    /// Console entry point and orchestration workflow for the BizTalk monitor config generator.
+    /// </summary>
     internal static class Program
     {
+        /// <summary>
+        /// Runs the generator once.
+        /// </summary>
+        /// <param name="args">Optional command-line arguments. The first argument may be the generator configuration path.</param>
+        /// <returns>The process exit code.</returns>
         private static int Main(string[] args)
         {
             GeneratorFileLogger logger = null;
             GeneratorEventLogger eventLogger = null;
+            string baseDirectory = null;
+            string configPath = null;
 
             try
             {
-                var baseDirectory = AppDomain.CurrentDomain.BaseDirectory;
-                var configPath = args != null && args.Length > 0 && !string.IsNullOrWhiteSpace(args[0])
+                baseDirectory = AppDomain.CurrentDomain.BaseDirectory;
+                configPath = args != null && args.Length > 0 && !string.IsNullOrWhiteSpace(args[0])
                     ? args[0]
                     : Path.Combine(baseDirectory, "generator-settings.json");
+                configPath = Path.GetFullPath(configPath);
+
+                WriteConsoleBanner("BizTalk Monitor Config Generator", configPath);
+                WriteConsoleInfo("Lade Generator-Konfiguration...");
 
                 var configuration = GeneratorConfiguration.Load(configPath);
                 configuration.Validate();
+                WriteConsoleInfo("Konfiguration geladen. Umgebung=" + configuration.EnvironmentName + ".");
 
                 var logDirectory = ResolvePath(baseDirectory, configuration.Logging.LogDirectory);
+                WriteConsoleInfo("Initialisiere Dateilog: " + BuildLogFilePreview(logDirectory, configuration.Logging.FilePrefix));
                 logger = new GeneratorFileLogger(logDirectory, configuration.Logging.FilePrefix, configuration.Logging.RetentionDays, configuration.GeneratorName, configuration.EnvironmentName);
                 logger.CleanupOldFiles();
                 logger.Info(configuration.GeneratorName + " gestartet. Umgebung=" + configuration.EnvironmentName + ", Server=" + Environment.MachineName + ".");
                 logger.Info("Generator-Konfiguration geladen: " + Path.GetFullPath(configPath));
+                logger.Info("Ausgabeziel: " + ResolvePath(baseDirectory, configuration.Output.Path));
 
+                WriteConsoleInfo("Initialisiere Windows Event Log. Quelle=" + configuration.EventLog.Source + ", Log=" + configuration.EventLog.LogName + ", Aktiv=" + configuration.EventLog.Enabled + ".");
                 eventLogger = new GeneratorEventLogger(configuration.EventLog, logger);
                 eventLogger.TryInitialize();
                 eventLogger.Info(configuration.GeneratorName + " gestartet. Umgebung=" + configuration.EnvironmentName + ", Server=" + Environment.MachineName + ".", 1000);
 
+                WriteConsoleInfo("Starte BizTalk-Discovery. SendPorts=" + configuration.BizTalk.IncludeSendPorts + ", ReceiveLocations=" + configuration.BizTalk.IncludeReceiveLocations + ".");
                 var discoveryService = new BizTalkCatalogDiscoveryService(configuration.BizTalk, configuration.Output, logger);
                 var discovered = discoveryService.Discover();
                 logger.Info("Discovery abgeschlossen. Gefundene unterstützte Targets=" + discovered.Count + ".");
+                WriteConsoleInfo("Discovery abgeschlossen. Gefundene unterstuetzte Targets=" + discovered.Count + ".");
 
                 var outputConfiguration = BuildMonitorConfiguration(configuration, discovered);
                 var outputPath = ResolvePath(baseDirectory, configuration.Output.Path);
+                WriteConsoleInfo("Schreibe Monitor-Konfiguration: " + outputPath);
                 JsonFileWriter.WritePrettyJsonAtomic(outputPath, outputConfiguration, configuration.Output.OverwriteExisting);
                 logger.Info("Monitor-Konfiguration geschrieben: " + outputPath);
                 eventLogger.InfoIfSuccessEnabled("Monitor-Konfiguration erfolgreich generiert: " + outputPath, 1001);
+                WriteConsoleInfo("Monitor-Konfiguration geschrieben.");
 
                 if (discovered.Count == 0)
                 {
                     var message = "Es wurden keine aktiven und unterstützten BizTalk-Endpunkte gefunden. Ausgabe wurde dennoch geschrieben: " + outputPath;
                     logger.Warn(message);
                     eventLogger.Summary(message, true);
+                    WriteConsoleWarn(message);
                     return configuration.Output.FailIfNoTargetsFound ? 2 : 0;
                 }
 
@@ -62,13 +85,21 @@ namespace BizTalkMonitorConfigGenerator
                     outputPath);
                 logger.Info(summary);
                 eventLogger.Summary(summary, false);
+                WriteConsoleInfo(summary);
                 return 0;
             }
             catch (Exception ex)
             {
+                WriteConsoleFatal("Generatorlauf fehlgeschlagen.", configPath, ex);
+
                 if (logger != null)
                 {
                     logger.Error("Fataler Fehler: " + ex.GetType().Name + ": " + ex.Message);
+                    logger.Error("Details: " + ex);
+                }
+                else
+                {
+                    TryWriteFallbackFailureLog(baseDirectory, configPath, ex);
                 }
 
                 if (eventLogger != null)
@@ -80,6 +111,12 @@ namespace BizTalkMonitorConfigGenerator
             }
         }
 
+        /// <summary>
+        /// Builds the final monitor configuration from the template and discovered endpoints.
+        /// </summary>
+        /// <param name="configuration">The generator configuration.</param>
+        /// <param name="discovered">The discovered BizTalk endpoints.</param>
+        /// <returns>The monitor configuration to write.</returns>
         private static MonitorConfiguration BuildMonitorConfiguration(GeneratorConfiguration configuration, IReadOnlyCollection<DiscoveredEndpoint> discovered)
         {
             var result = configuration.GeneratedMonitorConfig.CloneWithoutTargets();
@@ -114,6 +151,12 @@ namespace BizTalkMonitorConfigGenerator
             return result;
         }
 
+        /// <summary>
+        /// Resolves a configured path against the application base directory.
+        /// </summary>
+        /// <param name="baseDirectory">The application base directory.</param>
+        /// <param name="configuredPath">The configured relative or absolute path.</param>
+        /// <returns>The resolved path.</returns>
         private static string ResolvePath(string baseDirectory, string configuredPath)
         {
             if (Path.IsPathRooted(configuredPath))
@@ -123,5 +166,103 @@ namespace BizTalkMonitorConfigGenerator
 
             return Path.GetFullPath(Path.Combine(baseDirectory, configuredPath));
         }
+
+        /// <summary>
+        /// Writes the initial console banner before configuration and file logging are available.
+        /// </summary>
+        /// <param name="title">The program title.</param>
+        /// <param name="configPath">The resolved configuration path.</param>
+        private static void WriteConsoleBanner(string title, string configPath)
+        {
+            TryWriteConsoleLine(Console.Out, "============================================================");
+            TryWriteConsoleLine(Console.Out, title);
+            TryWriteConsoleLine(Console.Out, "Server: " + Environment.MachineName);
+            TryWriteConsoleLine(Console.Out, "Start:  " + DateTimeOffset.Now.ToString("yyyy-MM-dd HH:mm:ss zzz"));
+            TryWriteConsoleLine(Console.Out, "Config: " + (configPath ?? "(nicht aufgeloest)"));
+            TryWriteConsoleLine(Console.Out, "============================================================");
+        }
+
+        /// <summary>
+        /// Writes a console information message.
+        /// </summary>
+        /// <param name="message">The message to write.</param>
+        private static void WriteConsoleInfo(string message)
+        {
+            TryWriteConsoleLine(Console.Out, "[INFO] " + message);
+        }
+
+        /// <summary>
+        /// Writes a console warning message.
+        /// </summary>
+        /// <param name="message">The message to write.</param>
+        private static void WriteConsoleWarn(string message)
+        {
+            TryWriteConsoleLine(Console.Out, "[WARN] " + message);
+        }
+
+        /// <summary>
+        /// Writes a fatal console error with actionable context.
+        /// </summary>
+        /// <param name="message">The user-facing failure message.</param>
+        /// <param name="configPath">The configuration path used for the run.</param>
+        /// <param name="exception">The exception that ended the run.</param>
+        private static void WriteConsoleFatal(string message, string configPath, Exception exception)
+        {
+            TryWriteConsoleLine(Console.Error, "[ERROR] " + message);
+            TryWriteConsoleLine(Console.Error, "[ERROR] Konfiguration: " + (configPath ?? "(nicht aufgeloest)"));
+            TryWriteConsoleLine(Console.Error, "[ERROR] Ursache: " + exception.GetType().Name + ": " + exception.Message);
+            TryWriteConsoleLine(Console.Error, "[ERROR] Details: " + exception);
+        }
+
+        /// <summary>
+        /// Writes one line to a console writer and ignores secondary console failures.
+        /// </summary>
+        /// <param name="writer">The console writer.</param>
+        /// <param name="message">The line to write.</param>
+        private static void TryWriteConsoleLine(TextWriter writer, string message)
+        {
+            try
+            {
+                writer.WriteLine(message);
+            }
+            catch
+            {
+            }
+        }
+
+        /// <summary>
+        /// Writes a fallback fatal log when configured logging could not be initialized.
+        /// </summary>
+        /// <param name="baseDirectory">The application base directory.</param>
+        /// <param name="configPath">The configuration path used for the run.</param>
+        /// <param name="exception">The exception that ended the run.</param>
+        private static void TryWriteFallbackFailureLog(string baseDirectory, string configPath, Exception exception)
+        {
+            try
+            {
+                var directory = ResolvePath(baseDirectory ?? AppDomain.CurrentDomain.BaseDirectory, "logs");
+                var fallbackLogger = new GeneratorFileLogger(directory, "biztalk-monitor-config-generator-startup", 5, "BizTalkMonitorConfigGenerator", "Startup");
+                fallbackLogger.Error("Generator konnte nicht gestartet werden. Konfiguration=" + (configPath ?? "(nicht aufgeloest)") + ". Fehler=" + exception.GetType().Name + ": " + exception.Message);
+                fallbackLogger.Error("Details: " + exception);
+                WriteConsoleInfo("Fallback-Log geschrieben: " + BuildLogFilePreview(directory, "biztalk-monitor-config-generator-startup"));
+            }
+            catch (Exception fallbackEx)
+            {
+                TryWriteConsoleLine(Console.Error, "[ERROR] Fallback-Log konnte nicht geschrieben werden: " + fallbackEx.GetType().Name + ": " + fallbackEx.Message);
+            }
+        }
+
+        /// <summary>
+        /// Builds the expected daily log file path for console diagnostics.
+        /// </summary>
+        /// <param name="directory">The log directory.</param>
+        /// <param name="filePrefix">The rolling file prefix.</param>
+        /// <returns>The expected log file path for the current local date.</returns>
+        private static string BuildLogFilePreview(string directory, string filePrefix)
+        {
+            var safeDirectory = string.IsNullOrWhiteSpace(directory) ? AppDomain.CurrentDomain.BaseDirectory : directory;
+            var safePrefix = string.IsNullOrWhiteSpace(filePrefix) ? "biztalk-monitor-config-generator" : filePrefix;
+            return Path.Combine(safeDirectory, safePrefix + "-" + DateTime.Now.ToString("yyyy-MM-dd") + ".log");
+        }
     }
 }

src/BizTalkMonitorConfigGenerator/Properties/AssemblyInfo.cs

@@ -1,6 +1,7 @@
 using System.Reflection;
 using System.Runtime.InteropServices;
 
+// Assembly metadata for the BizTalkMonitorConfigGenerator console application.
 [assembly: AssemblyTitle("BizTalkMonitorConfigGenerator")]
 [assembly: AssemblyDescription("Generates HostAvailabilityMonitor JSON config from active BizTalk send ports and receive locations.")]
 [assembly: AssemblyConfiguration("")]

src/BizTalkMonitorConfigGenerator/Serialization/JsonFileWriter.cs

@@ -5,8 +5,17 @@ using System.Web.Script.Serialization;
 
 namespace BizTalkMonitorConfigGenerator.Serialization
 {
+    /// <summary>
+    /// Writes generator output JSON files with stable formatting and atomic replacement.
+    /// </summary>
     public static class JsonFileWriter
     {
+        /// <summary>
+        /// Serializes an object as pretty JSON and replaces the target file atomically.
+        /// </summary>
+        /// <param name="path">The target JSON file path.</param>
+        /// <param name="value">The value to serialize.</param>
+        /// <param name="overwriteExisting">True to replace an existing file; otherwise false.</param>
         public static void WritePrettyJsonAtomic(string path, object value, bool overwriteExisting)
         {
             if (string.IsNullOrWhiteSpace(path))
@@ -44,6 +53,11 @@ namespace BizTalkMonitorConfigGenerator.Serialization
             File.Move(tempPath, fullPath);
         }
 
+        /// <summary>
+        /// Formats compact JavaScriptSerializer JSON with indentation.
+        /// </summary>
+        /// <param name="json">The compact JSON string to format.</param>
+        /// <returns>The formatted JSON string.</returns>
         private static string PrettyPrint(string json)
         {
             if (string.IsNullOrWhiteSpace(json))
@@ -126,6 +140,11 @@ namespace BizTalkMonitorConfigGenerator.Serialization
             return sb.ToString();
         }
 
+        /// <summary>
+        /// Appends indentation spaces for the current JSON nesting level.
+        /// </summary>
+        /// <param name="sb">The output string builder.</param>
+        /// <param name="indent">The indentation level.</param>
         private static void AppendIndent(StringBuilder sb, int indent)
         {
             for (var i = 0; i < indent; i++)

src/HostAvailabilityMonitor/Configuration/HipVirtualMachineConfiguration.cs

@@ -5,10 +5,21 @@ using System.Web.Script.Serialization;
 
 namespace HostAvailabilityMonitor.Configuration
 {
+    /// <summary>
+    /// Represents the external HIP virtual machine configuration file.
+    /// </summary>
     public sealed class HipVirtualMachineConfiguration
     {
+        /// <summary>
+        /// Gets or sets the configured virtual machines.
+        /// </summary>
         public List<HipVirtualMachine> VirtualMachines { get; set; } = new List<HipVirtualMachine>();
 
+        /// <summary>
+        /// Loads and deserializes a HIP virtual machine configuration file.
+        /// </summary>
+        /// <param name="path">The JSON file path to load.</param>
+        /// <returns>The normalized HIP virtual machine configuration.</returns>
         public static HipVirtualMachineConfiguration Load(string path)
         {
             if (string.IsNullOrWhiteSpace(path))
@@ -34,12 +45,34 @@ namespace HostAvailabilityMonitor.Configuration
         }
     }
 
+    /// <summary>
+    /// Describes one HIP virtual machine and the checks that should be generated for it.
+    /// </summary>
     public sealed class HipVirtualMachine
     {
+        /// <summary>
+        /// Gets or sets the logical group used for reporting.
+        /// </summary>
         public string Group { get; set; } = string.Empty;
+
+        /// <summary>
+        /// Gets or sets the virtual machine display name.
+        /// </summary>
         public string Name { get; set; } = string.Empty;
+
+        /// <summary>
+        /// Gets or sets the host name or IP address to probe.
+        /// </summary>
         public string Address { get; set; } = string.Empty;
+
+        /// <summary>
+        /// Gets or sets an optional description for mail and summary output.
+        /// </summary>
         public string Description { get; set; } = string.Empty;
+
+        /// <summary>
+        /// Gets or sets a value indicating whether monitor targets should be generated for this VM.
+        /// </summary>
         public bool Enabled { get; set; } = true;
     }
 }

src/HostAvailabilityMonitor/Configuration/MonitorConfiguration.cs

@@ -6,17 +6,56 @@ using System.Web.Script.Serialization;
 
 namespace HostAvailabilityMonitor.Configuration
 {
+    /// <summary>
+    /// Root configuration for the host availability monitor.
+    /// </summary>
     public sealed class MonitorConfiguration
     {
+        /// <summary>
+        /// Gets or sets the monitor name shown in logs, event log entries and email.
+        /// </summary>
         public string ApplicationName { get; set; } = "HostAvailabilityMonitor";
+
+        /// <summary>
+        /// Gets or sets the environment label shown in logs, event log entries and email.
+        /// </summary>
         public string EnvironmentName { get; set; } = "Unspecified Environment";
+
+        /// <summary>
+        /// Gets or sets runtime behavior such as concurrency and state persistence.
+        /// </summary>
         public RuntimeOptions Runtime { get; set; } = new RuntimeOptions();
+
+        /// <summary>
+        /// Gets or sets rolling file log settings.
+        /// </summary>
         public LoggingOptions Logging { get; set; } = new LoggingOptions();
+
+        /// <summary>
+        /// Gets or sets Windows Application Event Log settings.
+        /// </summary>
         public EventLogOptions EventLog { get; set; } = new EventLogOptions();
+
+        /// <summary>
+        /// Gets or sets SMTP and notification settings.
+        /// </summary>
         public EmailOptions Email { get; set; } = new EmailOptions();
+
+        /// <summary>
+        /// Gets or sets optional static HIP virtual machine monitoring settings.
+        /// </summary>
         public HipVirtualMachineOptions HipVirtualMachines { get; set; } = new HipVirtualMachineOptions();
+
+        /// <summary>
+        /// Gets or sets the endpoint targets to probe.
+        /// </summary>
         public List<TargetOptions> Targets { get; set; } = new List<TargetOptions>();
 
+        /// <summary>
+        /// Loads and normalizes monitor configuration from a JSON file.
+        /// </summary>
+        /// <param name="path">The JSON configuration path.</param>
+        /// <returns>The normalized monitor configuration.</returns>
         public static MonitorConfiguration Load(string path)
         {
             if (!File.Exists(path))
@@ -84,6 +123,9 @@ namespace HostAvailabilityMonitor.Configuration
             return config;
         }
 
+        /// <summary>
+        /// Validates monitor settings and applies safe defaults where possible.
+        /// </summary>
         public void Validate()
         {
             Targets = Targets ?? new List<TargetOptions>();
@@ -177,6 +219,12 @@ namespace HostAvailabilityMonitor.Configuration
                 }
             }
         }
+
+        /// <summary>
+        /// Removes null, empty and duplicate recipient entries.
+        /// </summary>
+        /// <param name="values">The recipient list from configuration.</param>
+        /// <returns>A normalized recipient list.</returns>
         private static List<string> SanitizeRecipientList(List<string> values)
         {
             if (values == null)
@@ -191,6 +239,11 @@ namespace HostAvailabilityMonitor.Configuration
                 .ToList();
         }
 
+        /// <summary>
+        /// Counts all configured email recipients across To, Cc and Bcc.
+        /// </summary>
+        /// <param name="email">The email options to inspect.</param>
+        /// <returns>The number of configured recipients.</returns>
         private static int GetConfiguredRecipientCount(EmailOptions email)
         {
             if (email == null)
@@ -204,93 +257,330 @@ namespace HostAvailabilityMonitor.Configuration
         }
     }
 
+    /// <summary>
+    /// Defines monitor runtime behavior.
+    /// </summary>
     public sealed class RuntimeOptions
     {
+        /// <summary>
+        /// Gets or sets the maximum number of concurrent endpoint probes.
+        /// </summary>
         public int MaxConcurrency { get; set; } = 4;
+
+        /// <summary>
+        /// Gets or sets whether UNC checks should validate path access after the SMB port check.
+        /// </summary>
         public bool DefaultValidateUncPathAccess { get; set; } = false;
+
+        /// <summary>
+        /// Gets or sets whether endpoint failures should produce a non-zero process exit code.
+        /// </summary>
         public bool NonZeroExitCodeOnAnyFailure { get; set; } = false;
+
+        /// <summary>
+        /// Gets or sets whether execution errors should produce a non-zero process exit code.
+        /// </summary>
         public bool NonZeroExitCodeOnExecutionError { get; set; } = true;
+
+        /// <summary>
+        /// Gets or sets the state directory path.
+        /// </summary>
         public string StateDirectory { get; set; } = "state";
     }
 
+    /// <summary>
+    /// Defines rolling file log settings.
+    /// </summary>
     public sealed class LoggingOptions
     {
+        /// <summary>
+        /// Gets or sets the directory where monitor log files are written.
+        /// </summary>
         public string LogDirectory { get; set; } = "logs";
+
+        /// <summary>
+        /// Gets or sets the daily log file prefix.
+        /// </summary>
         public string FilePrefix { get; set; } = "host-availability-monitor";
+
+        /// <summary>
+        /// Gets or sets the number of daily log files to retain.
+        /// </summary>
         public int RetentionDays { get; set; } = 5;
     }
 
+    /// <summary>
+    /// Defines Windows Event Log behavior.
+    /// </summary>
     public sealed class EventLogOptions
     {
+        /// <summary>
+        /// Gets or sets a value indicating whether Event Log writes are enabled.
+        /// </summary>
         public bool Enabled { get; set; } = true;
+
+        /// <summary>
+        /// Gets or sets the Windows Event Log name.
+        /// </summary>
         public string LogName { get; set; } = "Application";
+
+        /// <summary>
+        /// Gets or sets the Event Log source name.
+        /// </summary>
         public string Source { get; set; } = "HostAvailabilityMonitor";
+
+        /// <summary>
+        /// Gets or sets whether the application should try to create the Event Log source.
+        /// </summary>
         public bool CreateSourceIfMissing { get; set; } = false;
+
+        /// <summary>
+        /// Gets or sets whether successful endpoint checks should be written to Event Log.
+        /// </summary>
         public bool WriteSuccessEntries { get; set; } = false;
+
+        /// <summary>
+        /// Gets or sets whether the run summary should be written to Event Log.
+        /// </summary>
         public bool WriteSummaryEntries { get; set; } = true;
     }
 
+    /// <summary>
+    /// Defines SMTP and notification behavior.
+    /// </summary>
     public sealed class EmailOptions
     {
+        /// <summary>
+        /// Gets or sets a value indicating whether email delivery is enabled.
+        /// </summary>
         public bool Enabled { get; set; } = false;
+
+        /// <summary>
+        /// Gets or sets the SMTP server host name.
+        /// </summary>
         public string SmtpHost { get; set; } = string.Empty;
+
+        /// <summary>
+        /// Gets or sets the SMTP server port.
+        /// </summary>
         public int SmtpPort { get; set; } = 25;
+
+        /// <summary>
+        /// Gets or sets whether SMTP should use SSL/TLS.
+        /// </summary>
         public bool UseSsl { get; set; } = false;
+
+        /// <summary>
+        /// Gets or sets whether default Windows credentials should be used for SMTP.
+        /// </summary>
         public bool UseDefaultCredentials { get; set; } = false;
+
+        /// <summary>
+        /// Gets or sets the SMTP user name when default credentials are disabled.
+        /// </summary>
         public string Username { get; set; } = string.Empty;
+
+        /// <summary>
+        /// Gets or sets the SMTP password when default credentials are disabled.
+        /// </summary>
         public string Password { get; set; } = string.Empty;
+
+        /// <summary>
+        /// Gets or sets the sender email address.
+        /// </summary>
         public string From { get; set; } = string.Empty;
+
+        /// <summary>
+        /// Gets or sets primary email recipients.
+        /// </summary>
         public List<string> To { get; set; } = new List<string>();
+
+        /// <summary>
+        /// Gets or sets CC email recipients.
+        /// </summary>
         public List<string> Cc { get; set; } = new List<string>();
+
+        /// <summary>
+        /// Gets or sets BCC email recipients.
+        /// </summary>
         public List<string> Bcc { get; set; } = new List<string>();
+
+        /// <summary>
+        /// Gets or sets the subject prefix used for all notification emails.
+        /// </summary>
         public string SubjectPrefix { get; set; } = "[HostAvailabilityMonitor]";
+
+        /// <summary>
+        /// Gets or sets whether failure notification emails should be sent.
+        /// </summary>
         public bool SendOnFailure { get; set; } = true;
+
+        /// <summary>
+        /// Gets or sets whether recovery notification emails should be sent.
+        /// </summary>
         public bool SendOnRecovery { get; set; } = true;
+
+        /// <summary>
+        /// Gets or sets whether the once-per-day summary email should be sent.
+        /// </summary>
         public bool SendDailySummary { get; set; } = false;
+
+        /// <summary>
+        /// Gets or sets the local server hour at or after which the daily summary may be sent.
+        /// </summary>
         public int DailySummaryHourLocal { get; set; } = 14;
+
+        /// <summary>
+        /// Gets or sets the local server minute at or after which the daily summary may be sent.
+        /// </summary>
         public int DailySummaryMinuteLocal { get; set; } = 0;
+
+        /// <summary>
+        /// Gets or sets whether failure and recovery emails should only be sent on state changes.
+        /// </summary>
         public bool OnlyOnStateChange { get; set; } = true;
+
+        /// <summary>
+        /// Gets or sets the cooldown in minutes for repeated failure emails.
+        /// </summary>
         public int CooldownMinutes { get; set; } = 0;
+
+        /// <summary>
+        /// Gets or sets the SMTP timeout in seconds.
+        /// </summary>
         public int TimeoutSeconds { get; set; } = 30;
     }
 
+    /// <summary>
+    /// Defines optional static HIP virtual machine probe generation.
+    /// </summary>
     public sealed class HipVirtualMachineOptions
     {
+        /// <summary>
+        /// Gets or sets whether HIP virtual machine checks are enabled.
+        /// </summary>
         public bool Enabled { get; set; } = false;
+
+        /// <summary>
+        /// Gets or sets the HIP VM JSON configuration path.
+        /// </summary>
         public string ConfigPath { get; set; } = "hip-vms.json";
+
+        /// <summary>
+        /// Gets or sets the application name assigned to generated HIP VM targets.
+        /// </summary>
         public string ApplicationName { get; set; } = "HIP Virtual Machines";
+
+        /// <summary>
+        /// Gets or sets the timeout in seconds for generated HIP VM targets.
+        /// </summary>
         public int TimeoutSeconds { get; set; } = 5;
+
+        /// <summary>
+        /// Gets or sets the RDP port used for generated RDP checks.
+        /// </summary>
         public int RdpPort { get; set; } = 3389;
+
+        /// <summary>
+        /// Gets or sets whether ICMP network checks should be generated.
+        /// </summary>
         public bool CheckNetwork { get; set; } = true;
+
+        /// <summary>
+        /// Gets or sets whether RDP TCP checks should be generated.
+        /// </summary>
         public bool CheckRdp { get; set; } = true;
     }
 
+    /// <summary>
+    /// Defines one endpoint target that can be probed by the monitor.
+    /// </summary>
     public sealed class TargetOptions
     {
+        /// <summary>
+        /// Gets or sets the configured target name.
+        /// </summary>
         public string Name { get; set; } = string.Empty;
+
+        /// <summary>
+        /// Gets or sets the logical application owning the target.
+        /// </summary>
         public string ApplicationName { get; set; } = string.Empty;
+
+        /// <summary>
+        /// Gets or sets the endpoint address to probe.
+        /// </summary>
         public string Endpoint { get; set; } = string.Empty;
+
+        /// <summary>
+        /// Gets or sets the probe timeout in seconds.
+        /// </summary>
         public int TimeoutSeconds { get; set; } = 10;
+
+        /// <summary>
+        /// Gets or sets an optional explicit port override.
+        /// </summary>
         public int? Port { get; set; }
+
+        /// <summary>
+        /// Gets or sets an optional UNC path access validation override.
+        /// </summary>
         public bool? ValidateUncPathAccess { get; set; }
+
+        /// <summary>
+        /// Gets or sets the HTTP method used for HTTP and HTTPS probes.
+        /// </summary>
         public string HttpMethod { get; set; }
+
+        /// <summary>
+        /// Gets or sets the source that created the target.
+        /// </summary>
         public string Source { get; set; }
+
+        /// <summary>
+        /// Gets or sets an optional group label for reporting.
+        /// </summary>
         public string Group { get; set; }
+
+        /// <summary>
+        /// Gets or sets an optional target description.
+        /// </summary>
         public string Description { get; set; }
+
+        /// <summary>
+        /// Gets or sets an optional machine name for generated VM targets.
+        /// </summary>
         public string MachineName { get; set; }
+
+        /// <summary>
+        /// Gets or sets an optional check name for generated targets.
+        /// </summary>
         public string CheckName { get; set; }
+
+        /// <summary>
+        /// Gets or sets a value indicating whether the target should be probed.
+        /// </summary>
         public bool Enabled { get; set; } = true;
 
+        /// <summary>
+        /// Gets the display name used in logs, status and notification output.
+        /// </summary>
         public string DisplayName
         {
             get { return string.IsNullOrWhiteSpace(Name) ? Endpoint : Name; }
         }
 
+        /// <summary>
+        /// Gets the normalized application name used for grouping.
+        /// </summary>
         public string EffectiveApplicationName
         {
             get { return string.IsNullOrWhiteSpace(ApplicationName) ? "Unassigned Application" : ApplicationName.Trim(); }
         }
 
+        /// <summary>
+        /// Gets the stable state key used to persist target state across runs.
+        /// </summary>
         public string StateKey
         {
             get
@@ -307,6 +597,11 @@ namespace HostAvailabilityMonitor.Configuration
             }
         }
 
+        /// <summary>
+        /// Trims a string for state-key generation.
+        /// </summary>
+        /// <param name="value">The configured value to normalize.</param>
+        /// <returns>The trimmed value, or an empty string for null and whitespace.</returns>
         private static string Normalize(string value)
         {
             return string.IsNullOrWhiteSpace(value) ? string.Empty : value.Trim();

src/HostAvailabilityMonitor/Logging/FileLogger.cs

@@ -7,15 +7,49 @@ using HostAvailabilityMonitor.Monitoring;
 
 namespace HostAvailabilityMonitor.Logging
 {
+    /// <summary>
+    /// Writes rolling monitor log files with daily file names and probe-specific fields.
+    /// </summary>
     public sealed class FileLogger
     {
+        /// <summary>
+        /// Synchronizes writes within the current process.
+        /// </summary>
         private readonly object _sync = new object();
+
+        /// <summary>
+        /// Directory where log files are stored.
+        /// </summary>
         private readonly string _directory;
+
+        /// <summary>
+        /// Prefix used for daily log file names.
+        /// </summary>
         private readonly string _filePrefix;
+
+        /// <summary>
+        /// Number of daily log files to retain.
+        /// </summary>
         private readonly int _retentionDays;
+
+        /// <summary>
+        /// Monitor name included in structured probe log fields.
+        /// </summary>
         private readonly string _monitorName;
+
+        /// <summary>
+        /// Environment name included in structured probe log fields.
+        /// </summary>
         private readonly string _environmentName;
 
+        /// <summary>
+        /// Initializes a new rolling file logger.
+        /// </summary>
+        /// <param name="directory">The target log directory.</param>
+        /// <param name="filePrefix">The daily log file prefix.</param>
+        /// <param name="retentionDays">The number of daily log files to retain.</param>
+        /// <param name="monitorName">The monitor name written to probe log lines.</param>
+        /// <param name="environmentName">The environment name written to probe log lines.</param>
         public FileLogger(string directory, string filePrefix, int retentionDays, string monitorName, string environmentName)
         {
             _directory = directory;
@@ -27,6 +61,9 @@ namespace HostAvailabilityMonitor.Logging
             Directory.CreateDirectory(_directory);
         }
 
+        /// <summary>
+        /// Deletes old rolling log files according to the retention setting.
+        /// </summary>
         public void CleanupOldFiles()
         {
             if (_retentionDays <= 0)
@@ -63,21 +100,37 @@ namespace HostAvailabilityMonitor.Logging
             }
         }
 
+        /// <summary>
+        /// Writes an informational log entry.
+        /// </summary>
+        /// <param name="message">The message to write.</param>
         public void Info(string message)
         {
             Write("INFO", message);
         }
 
+        /// <summary>
+        /// Writes a warning log entry.
+        /// </summary>
+        /// <param name="message">The message to write.</param>
         public void Warn(string message)
         {
             Write("WARN", message);
         }
 
+        /// <summary>
+        /// Writes an error log entry.
+        /// </summary>
+        /// <param name="message">The message to write.</param>
         public void Error(string message)
         {
             Write("ERROR", message);
         }
 
+        /// <summary>
+        /// Writes a structured probe result entry.
+        /// </summary>
+        /// <param name="result">The probe result to write.</param>
         public void Probe(ProbeResult result)
         {
             var level = result.IsSkipped ? "SKIP" : (result.IsSuccess ? "SUCCESS" : "FAIL");
@@ -137,6 +190,11 @@ namespace HostAvailabilityMonitor.Logging
             Write(level, string.Join(" | ", parts));
         }
 
+        /// <summary>
+        /// Formats and appends a log line.
+        /// </summary>
+        /// <param name="level">The log level text.</param>
+        /// <param name="message">The formatted message payload.</param>
         private void Write(string level, string message)
         {
             var line = string.Format(
@@ -155,6 +213,11 @@ namespace HostAvailabilityMonitor.Logging
             }
         }
 
+        /// <summary>
+        /// Appends a line to a file and retries transient file access failures.
+        /// </summary>
+        /// <param name="path">The log file path.</param>
+        /// <param name="line">The full line to append.</param>
         private void AppendWithRetries(string path, string line)
         {
             Exception lastException = null;
@@ -184,12 +247,22 @@ namespace HostAvailabilityMonitor.Logging
             }
         }
 
+        /// <summary>
+        /// Builds the daily log file path for the current local date.
+        /// </summary>
+        /// <returns>The current log file path.</returns>
         private string GetCurrentLogFilePath()
         {
             var fileName = _filePrefix + "-" + DateTime.Now.ToString("yyyy-MM-dd", CultureInfo.InvariantCulture) + ".log";
             return Path.Combine(_directory, fileName);
         }
 
+        /// <summary>
+        /// Extracts the date encoded in a rolling log file name.
+        /// </summary>
+        /// <param name="path">The log file path to inspect.</param>
+        /// <param name="date">The parsed file date when parsing succeeds.</param>
+        /// <returns>True when the date could be parsed; otherwise false.</returns>
         private bool TryGetDateFromFileName(string path, out DateTime date)
         {
             date = DateTime.MinValue;
@@ -204,6 +277,11 @@ namespace HostAvailabilityMonitor.Logging
             return DateTime.TryParseExact(datePart, "yyyy-MM-dd", CultureInfo.InvariantCulture, DateTimeStyles.None, out date);
         }
 
+        /// <summary>
+        /// Removes line breaks from values before they are written to one-line logs.
+        /// </summary>
+        /// <param name="value">The value to escape.</param>
+        /// <returns>The log-safe value.</returns>
         private static string Escape(string value)
         {
             return (value ?? string.Empty).Replace("\r", " ").Replace("\n", " ");

src/HostAvailabilityMonitor/Logging/WindowsEventLogger.cs

@@ -3,24 +3,46 @@ using System.Diagnostics;
 using System.Security;
 using HostAvailabilityMonitor.Configuration;
 
-namespace HostAvailabilityMonitor.Logging
-{
-    public sealed class WindowsEventLogger
-    {
-        private readonly EventLogOptions _options;
-        private readonly FileLogger _fallbackLogger;
-        private bool _disabled;
-
-        public WindowsEventLogger(EventLogOptions options, FileLogger fallbackLogger)
-        {
-            _options = options;
+namespace HostAvailabilityMonitor.Logging
+{
+    /// <summary>
+    /// Best-effort Windows Event Log writer for monitor lifecycle, probe and summary events.
+    /// </summary>
+    public sealed class WindowsEventLogger
+    {
+        /// <summary>
+        /// Event Log settings from monitor configuration.
+        /// </summary>
+        private readonly EventLogOptions _options;
+
+        /// <summary>
+        /// File logger used when Event Log writes fail.
+        /// </summary>
+        private readonly FileLogger _fallbackLogger;
+
+        /// <summary>
+        /// Indicates that Event Log writing has been disabled for this process.
+        /// </summary>
+        private bool _disabled;
+
+        /// <summary>
+        /// Initializes a new Windows Event Log writer.
+        /// </summary>
+        /// <param name="options">The Event Log configuration.</param>
+        /// <param name="fallbackLogger">The fallback file logger.</param>
+        public WindowsEventLogger(EventLogOptions options, FileLogger fallbackLogger)
+        {
+            _options = options;
             _fallbackLogger = fallbackLogger;
-            _disabled = !_options.Enabled;
-        }
-
-        public void TryInitialize()
-        {
-            if (_disabled)
+            _disabled = !_options.Enabled;
+        }
+
+        /// <summary>
+        /// Optionally creates the configured Event Log source.
+        /// </summary>
+        public void TryInitialize()
+        {
+            if (_disabled)
             {
                 return;
             }
@@ -46,35 +68,60 @@ namespace HostAvailabilityMonitor.Logging
             catch (Exception ex)
             {
                 _fallbackLogger.Warn("EventLog-Initialisierung konnte die Quelle nicht anlegen. " + ex.GetType().Name + ": " + ex.Message);
-            }
-        }
-
-        public void Info(string message, int eventId)
-        {
-            Write(message, EventLogEntryType.Information, eventId, forceWrite: true);
-        }
-
-        public void InfoIfSuccessEnabled(string message, int eventId)
-        {
-            if (_options.WriteSuccessEntries)
+            }
+        }
+
+        /// <summary>
+        /// Writes an informational event.
+        /// </summary>
+        /// <param name="message">The event message.</param>
+        /// <param name="eventId">The event identifier.</param>
+        public void Info(string message, int eventId)
+        {
+            Write(message, EventLogEntryType.Information, eventId, forceWrite: true);
+        }
+
+        /// <summary>
+        /// Writes an informational event only when success entries are enabled.
+        /// </summary>
+        /// <param name="message">The event message.</param>
+        /// <param name="eventId">The event identifier.</param>
+        public void InfoIfSuccessEnabled(string message, int eventId)
+        {
+            if (_options.WriteSuccessEntries)
             {
                 Write(message, EventLogEntryType.Information, eventId, forceWrite: true);
-            }
-        }
-
-        public void Warning(string message, int eventId)
-        {
-            Write(message, EventLogEntryType.Warning, eventId, forceWrite: true);
-        }
-
-        public void Error(string message, int eventId)
-        {
-            Write(message, EventLogEntryType.Error, eventId, forceWrite: true);
-        }
-
-        public void Summary(string message, bool hasFailures)
-        {
-            if (!_options.WriteSummaryEntries)
+            }
+        }
+
+        /// <summary>
+        /// Writes a warning event.
+        /// </summary>
+        /// <param name="message">The event message.</param>
+        /// <param name="eventId">The event identifier.</param>
+        public void Warning(string message, int eventId)
+        {
+            Write(message, EventLogEntryType.Warning, eventId, forceWrite: true);
+        }
+
+        /// <summary>
+        /// Writes an error event.
+        /// </summary>
+        /// <param name="message">The event message.</param>
+        /// <param name="eventId">The event identifier.</param>
+        public void Error(string message, int eventId)
+        {
+            Write(message, EventLogEntryType.Error, eventId, forceWrite: true);
+        }
+
+        /// <summary>
+        /// Writes a run summary event when summary entries are enabled.
+        /// </summary>
+        /// <param name="message">The summary message.</param>
+        /// <param name="hasFailures">True when the summary should be written as a warning.</param>
+        public void Summary(string message, bool hasFailures)
+        {
+            if (!_options.WriteSummaryEntries)
             {
                 return;
             }
@@ -83,12 +130,19 @@ namespace HostAvailabilityMonitor.Logging
                 message,
                 hasFailures ? EventLogEntryType.Warning : EventLogEntryType.Information,
                 hasFailures ? 2100 : 1100,
-                forceWrite: true);
-        }
-
-        private void Write(string message, EventLogEntryType entryType, int eventId, bool forceWrite)
-        {
-            if (_disabled || !forceWrite)
+                forceWrite: true);
+        }
+
+        /// <summary>
+        /// Writes one Event Log entry and disables future Event Log writes on failure.
+        /// </summary>
+        /// <param name="message">The event message.</param>
+        /// <param name="entryType">The Windows Event Log entry type.</param>
+        /// <param name="eventId">The event identifier.</param>
+        /// <param name="forceWrite">True to write the event when the logger is enabled.</param>
+        private void Write(string message, EventLogEntryType entryType, int eventId, bool forceWrite)
+        {
+            if (_disabled || !forceWrite)
             {
                 return;
             }
@@ -108,12 +162,16 @@ namespace HostAvailabilityMonitor.Logging
             catch (Exception ex)
             {
                 DisableAndFallback("EventLog-Schreiben fehlgeschlagen. " + ex.GetType().Name + ": " + ex.Message);
-            }
-        }
-
-        private void DisableAndFallback(string reason)
-        {
-            if (_disabled)
+            }
+        }
+
+        /// <summary>
+        /// Disables Event Log writes and records the reason in the fallback log.
+        /// </summary>
+        /// <param name="reason">The reason Event Log writes were disabled.</param>
+        private void DisableAndFallback(string reason)
+        {
+            if (_disabled)
             {
                 return;
             }

src/HostAvailabilityMonitor/Monitoring/EndpointProbeService.cs

@@ -10,17 +10,37 @@ using HostAvailabilityMonitor.Configuration;
 
 namespace HostAvailabilityMonitor.Monitoring
 {
+    /// <summary>
+    /// Executes endpoint probes for all supported target kinds.
+    /// </summary>
     public sealed class EndpointProbeService
     {
+        /// <summary>
+        /// Shared HTTP client with per-request timeout handling through cancellation tokens.
+        /// </summary>
         private static readonly HttpClient HttpClient = CreateHttpClient();
+
+        /// <summary>
+        /// Runtime options that influence probe behavior.
+        /// </summary>
         private readonly RuntimeOptions _runtimeOptions;
 
+        /// <summary>
+        /// Initializes a new endpoint probe service.
+        /// </summary>
+        /// <param name="runtimeOptions">Runtime options used for defaults such as UNC validation.</param>
         public EndpointProbeService(RuntimeOptions runtimeOptions)
         {
             _runtimeOptions = runtimeOptions ?? new RuntimeOptions();
             ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls | SecurityProtocolType.Tls11 | SecurityProtocolType.Tls12;
         }
 
+        /// <summary>
+        /// Probes one target by resolving its endpoint syntax to the appropriate check implementation.
+        /// </summary>
+        /// <param name="target">The target configuration to probe.</param>
+        /// <param name="cancellationToken">A token that can cancel the probe.</param>
+        /// <returns>The probe result for the target.</returns>
         public async Task<ProbeResult> ProbeAsync(TargetOptions target, CancellationToken cancellationToken)
         {
             var startedAt = DateTimeOffset.Now;
@@ -88,6 +108,14 @@ namespace HostAvailabilityMonitor.Monitoring
             }
         }
 
+        /// <summary>
+        /// Probes a plain host value by using TCP when a port is configured, otherwise ICMP.
+        /// </summary>
+        /// <param name="target">The target configuration.</param>
+        /// <param name="host">The host name or address.</param>
+        /// <param name="startedAt">The local start time of the probe.</param>
+        /// <param name="cancellationToken">A token that can cancel the probe.</param>
+        /// <returns>The probe result.</returns>
         private async Task<ProbeResult> CheckPlainHostAsync(TargetOptions target, string host, DateTimeOffset startedAt, CancellationToken cancellationToken)
         {
             if (target.Port.HasValue)
@@ -98,6 +126,14 @@ namespace HostAvailabilityMonitor.Monitoring
             return await CheckIcmpAsync(target, host, startedAt, host, cancellationToken).ConfigureAwait(false);
         }
 
+        /// <summary>
+        /// Probes a file URI by routing UNC-like URIs to UNC checks and local paths to file checks.
+        /// </summary>
+        /// <param name="target">The target configuration.</param>
+        /// <param name="uri">The file URI to probe.</param>
+        /// <param name="startedAt">The local start time of the probe.</param>
+        /// <param name="cancellationToken">A token that can cancel the probe.</param>
+        /// <returns>The probe result.</returns>
         private async Task<ProbeResult> CheckFileUriAsync(TargetOptions target, Uri uri, DateTimeOffset startedAt, CancellationToken cancellationToken)
         {
             if (uri.IsUnc || !string.IsNullOrWhiteSpace(uri.Host))
@@ -115,6 +151,14 @@ namespace HostAvailabilityMonitor.Monitoring
             return await CheckLocalPathAsync(target, localPath, startedAt, cancellationToken).ConfigureAwait(false);
         }
 
+        /// <summary>
+        /// Checks whether a local file or directory exists within the configured timeout.
+        /// </summary>
+        /// <param name="target">The target configuration.</param>
+        /// <param name="path">The local file system path.</param>
+        /// <param name="startedAt">The local start time of the probe.</param>
+        /// <param name="cancellationToken">A token that can cancel the probe.</param>
+        /// <returns>The probe result.</returns>
         private async Task<ProbeResult> CheckLocalPathAsync(TargetOptions target, string path, DateTimeOffset startedAt, CancellationToken cancellationToken)
         {
             try
@@ -139,6 +183,14 @@ namespace HostAvailabilityMonitor.Monitoring
             }
         }
 
+        /// <summary>
+        /// Checks a UNC target by validating SMB reachability and optionally path access.
+        /// </summary>
+        /// <param name="target">The target configuration.</param>
+        /// <param name="endpoint">The UNC endpoint path.</param>
+        /// <param name="startedAt">The local start time of the probe.</param>
+        /// <param name="cancellationToken">A token that can cancel the probe.</param>
+        /// <returns>The probe result.</returns>
         private async Task<ProbeResult> CheckUncAsync(TargetOptions target, string endpoint, DateTimeOffset startedAt, CancellationToken cancellationToken)
         {
             var host = ExtractUncServer(endpoint);
@@ -178,6 +230,15 @@ namespace HostAvailabilityMonitor.Monitoring
             }
         }
 
+        /// <summary>
+        /// Checks an HTTP or HTTPS endpoint and falls back from HEAD to GET when required.
+        /// </summary>
+        /// <param name="target">The target configuration.</param>
+        /// <param name="uri">The HTTP or HTTPS URI.</param>
+        /// <param name="startedAt">The local start time of the probe.</param>
+        /// <param name="kind">The resolved HTTP target kind.</param>
+        /// <param name="cancellationToken">A token that can cancel the probe.</param>
+        /// <returns>The probe result.</returns>
         private async Task<ProbeResult> CheckHttpAsync(TargetOptions target, Uri uri, DateTimeOffset startedAt, TargetKind kind, CancellationToken cancellationToken)
         {
             var methodText = string.IsNullOrWhiteSpace(target.HttpMethod) ? "HEAD" : target.HttpMethod.Trim().ToUpperInvariant();
@@ -220,6 +281,15 @@ namespace HostAvailabilityMonitor.Monitoring
             }
         }
 
+        /// <summary>
+        /// Retries an HTTP endpoint with GET after HEAD was rejected or failed.
+        /// </summary>
+        /// <param name="target">The target configuration.</param>
+        /// <param name="uri">The HTTP or HTTPS URI.</param>
+        /// <param name="startedAt">The local start time of the probe.</param>
+        /// <param name="kind">The resolved HTTP target kind.</param>
+        /// <param name="cancellationToken">A token that can cancel the probe.</param>
+        /// <returns>The probe result.</returns>
         private async Task<ProbeResult> RetryHttpWithGetAsync(TargetOptions target, Uri uri, DateTimeOffset startedAt, TargetKind kind, CancellationToken cancellationToken)
         {
             using (var timeoutCts = CancellationTokenSource.CreateLinkedTokenSource(cancellationToken))
@@ -244,6 +314,17 @@ namespace HostAvailabilityMonitor.Monitoring
             }
         }
 
+        /// <summary>
+        /// Checks TCP connectivity to a host and port.
+        /// </summary>
+        /// <param name="target">The target configuration.</param>
+        /// <param name="host">The host name or address.</param>
+        /// <param name="port">The target TCP port.</param>
+        /// <param name="startedAt">The local start time of the probe.</param>
+        /// <param name="kind">The resolved target kind.</param>
+        /// <param name="endpoint">The endpoint string reported in the result.</param>
+        /// <param name="cancellationToken">A token that can cancel the probe.</param>
+        /// <returns>The probe result.</returns>
         private async Task<ProbeResult> CheckTcpAsync(TargetOptions target, string host, int? port, DateTimeOffset startedAt, TargetKind kind, string endpoint, CancellationToken cancellationToken)
         {
             if (string.IsNullOrWhiteSpace(host))
@@ -299,6 +380,15 @@ namespace HostAvailabilityMonitor.Monitoring
             }
         }
 
+        /// <summary>
+        /// Checks ICMP reachability with the configured timeout.
+        /// </summary>
+        /// <param name="target">The target configuration.</param>
+        /// <param name="host">The host name or address.</param>
+        /// <param name="startedAt">The local start time of the probe.</param>
+        /// <param name="endpoint">The endpoint string reported in the result.</param>
+        /// <param name="cancellationToken">A token that can cancel the probe.</param>
+        /// <returns>The probe result.</returns>
         private async Task<ProbeResult> CheckIcmpAsync(TargetOptions target, string host, DateTimeOffset startedAt, string endpoint, CancellationToken cancellationToken)
         {
             using (var ping = new Ping())
@@ -332,6 +422,12 @@ namespace HostAvailabilityMonitor.Monitoring
             }
         }
 
+        /// <summary>
+        /// Resolves the effective port for a URI.
+        /// </summary>
+        /// <param name="uri">The URI being probed.</param>
+        /// <param name="defaultPort">The default port for the target kind.</param>
+        /// <returns>The explicit URI port, the default port, or null.</returns>
         private static int? ResolvePort(Uri uri, int? defaultPort)
         {
             if (uri == null)
@@ -347,6 +443,11 @@ namespace HostAvailabilityMonitor.Monitoring
             return defaultPort;
         }
 
+        /// <summary>
+        /// Extracts the server component from a UNC path.
+        /// </summary>
+        /// <param name="endpoint">The UNC path.</param>
+        /// <returns>The server component, or an empty string.</returns>
         private static string ExtractUncServer(string endpoint)
         {
             if (string.IsNullOrWhiteSpace(endpoint))
@@ -359,6 +460,10 @@ namespace HostAvailabilityMonitor.Monitoring
             return firstSeparator >= 0 ? trimmed.Substring(0, firstSeparator) : trimmed;
         }
 
+        /// <summary>
+        /// Creates the shared HTTP client used by all HTTP probes.
+        /// </summary>
+        /// <returns>A configured HTTP client.</returns>
         private static HttpClient CreateHttpClient()
         {
             var handler = new HttpClientHandler();
@@ -367,21 +472,70 @@ namespace HostAvailabilityMonitor.Monitoring
             return client;
         }
 
+        /// <summary>
+        /// Creates a successful probe result.
+        /// </summary>
+        /// <param name="target">The target configuration.</param>
+        /// <param name="kind">The resolved target kind.</param>
+        /// <param name="endpoint">The endpoint reported in the result.</param>
+        /// <param name="startedAt">The local start time of the probe.</param>
+        /// <param name="host">The resolved host.</param>
+        /// <param name="port">The resolved port.</param>
+        /// <param name="detail">The result detail text.</param>
+        /// <param name="httpStatusCode">The HTTP status code, when applicable.</param>
+        /// <returns>The successful probe result.</returns>
         private static ProbeResult Success(TargetOptions target, TargetKind kind, string endpoint, DateTimeOffset startedAt, string host, int? port, string detail, int? httpStatusCode)
         {
             return BuildResult(target, kind, endpoint, startedAt, true, false, "Reachable", detail, host, port, httpStatusCode, null);
         }
 
+        /// <summary>
+        /// Creates a failed probe result.
+        /// </summary>
+        /// <param name="target">The target configuration.</param>
+        /// <param name="kind">The resolved target kind.</param>
+        /// <param name="endpoint">The endpoint reported in the result.</param>
+        /// <param name="startedAt">The local start time of the probe.</param>
+        /// <param name="detail">The result detail text.</param>
+        /// <param name="ex">The exception that caused the failure, if any.</param>
+        /// <param name="host">The resolved host.</param>
+        /// <param name="port">The resolved port.</param>
+        /// <returns>The failed probe result.</returns>
         private static ProbeResult Fail(TargetOptions target, TargetKind kind, string endpoint, DateTimeOffset startedAt, string detail, Exception ex, string host, int? port)
         {
             return BuildResult(target, kind, endpoint, startedAt, false, false, "Unreachable", detail, host, port, null, ex == null ? null : ex.GetType().Name);
         }
 
+        /// <summary>
+        /// Creates a skipped probe result.
+        /// </summary>
+        /// <param name="target">The target configuration.</param>
+        /// <param name="kind">The resolved target kind.</param>
+        /// <param name="endpoint">The endpoint reported in the result.</param>
+        /// <param name="startedAt">The local start time of the probe.</param>
+        /// <param name="detail">The skip reason.</param>
+        /// <returns>The skipped probe result.</returns>
         private static ProbeResult Skip(TargetOptions target, TargetKind kind, string endpoint, DateTimeOffset startedAt, string detail)
         {
             return BuildResult(target, kind, endpoint, startedAt, false, true, "Skipped", detail, null, null, null, null);
         }
 
+        /// <summary>
+        /// Creates the common probe result object.
+        /// </summary>
+        /// <param name="target">The target configuration.</param>
+        /// <param name="kind">The resolved target kind.</param>
+        /// <param name="endpoint">The endpoint reported in the result.</param>
+        /// <param name="startedAt">The local start time of the probe.</param>
+        /// <param name="isSuccess">True when the probe succeeded.</param>
+        /// <param name="isSkipped">True when the target was intentionally skipped.</param>
+        /// <param name="statusText">The high-level status text.</param>
+        /// <param name="detail">The detailed result text.</param>
+        /// <param name="host">The resolved host.</param>
+        /// <param name="port">The resolved port.</param>
+        /// <param name="httpStatusCode">The HTTP status code, when applicable.</param>
+        /// <param name="errorType">The exception type, when applicable.</param>
+        /// <returns>The populated probe result.</returns>
         private static ProbeResult BuildResult(TargetOptions target, TargetKind kind, string endpoint, DateTimeOffset startedAt, bool isSuccess, bool isSkipped, string statusText, string detail, string host, int? port, int? httpStatusCode, string errorType)
         {
             return new ProbeResult
@@ -409,6 +563,14 @@ namespace HostAvailabilityMonitor.Monitoring
             };
         }
 
+        /// <summary>
+        /// Creates a skipped result for endpoints that should not be network-probed.
+        /// </summary>
+        /// <param name="target">The target configuration.</param>
+        /// <param name="endpoint">The endpoint value to inspect.</param>
+        /// <param name="startedAt">The local start time of the probe.</param>
+        /// <param name="result">The skipped result when a skip rule matches.</param>
+        /// <returns>True when a skip result was created; otherwise false.</returns>
         private static bool TryCreateSkipResult(TargetOptions target, string endpoint, DateTimeOffset startedAt, out ProbeResult result)
         {
             result = null;
@@ -422,6 +584,12 @@ namespace HostAvailabilityMonitor.Monitoring
             return false;
         }
 
+        /// <summary>
+        /// Detects BizTalk SMTP adapter targets that contain recipient lists instead of network endpoints.
+        /// </summary>
+        /// <param name="target">The target configuration.</param>
+        /// <param name="endpoint">The endpoint value to inspect.</param>
+        /// <returns>True when the target looks like an SMTP recipient list.</returns>
         private static bool LooksLikeSmtpAdapterTarget(TargetOptions target, string endpoint)
         {
             var name = target == null ? string.Empty : (target.Name ?? string.Empty);
@@ -435,6 +603,11 @@ namespace HostAvailabilityMonitor.Monitoring
             return LooksLikeEmailAddressList(value);
         }
 
+        /// <summary>
+        /// Detects semicolon-separated email recipient lists that are not monitorable endpoints.
+        /// </summary>
+        /// <param name="value">The endpoint value to inspect.</param>
+        /// <returns>True when the value looks like an email address list.</returns>
         private static bool LooksLikeEmailAddressList(string value)
         {
             if (string.IsNullOrWhiteSpace(value))
@@ -482,6 +655,14 @@ namespace HostAvailabilityMonitor.Monitoring
             return true;
         }
 
+        /// <summary>
+        /// Awaits a task until it completes or the timeout expires.
+        /// </summary>
+        /// <typeparam name="T">The task result type.</typeparam>
+        /// <param name="task">The task to await.</param>
+        /// <param name="timeout">The maximum wait time.</param>
+        /// <param name="cancellationToken">A token that can cancel the wait.</param>
+        /// <returns>A completion result containing the task result when it completed in time.</returns>
         private static async Task<CompletionResult<T>> CompleteWithinAsync<T>(Task<T> task, TimeSpan timeout, CancellationToken cancellationToken)
         {
             var delayTask = Task.Delay(timeout, cancellationToken);
@@ -494,6 +675,13 @@ namespace HostAvailabilityMonitor.Monitoring
             return new CompletionResult<T>(true, await task.ConfigureAwait(false));
         }
 
+        /// <summary>
+        /// Awaits a non-generic task until it completes or the timeout expires.
+        /// </summary>
+        /// <param name="task">The task to await.</param>
+        /// <param name="timeout">The maximum wait time.</param>
+        /// <param name="cancellationToken">A token that can cancel the wait.</param>
+        /// <returns>A completion result indicating whether the task completed in time.</returns>
         private static async Task<CompletionResult<bool>> CompleteWithinAsync(Task task, TimeSpan timeout, CancellationToken cancellationToken)
         {
             var delayTask = Task.Delay(timeout, cancellationToken);
@@ -507,15 +695,31 @@ namespace HostAvailabilityMonitor.Monitoring
             return new CompletionResult<bool>(true, true);
         }
 
+        /// <summary>
+        /// Holds the outcome of a timeout-wrapped task.
+        /// </summary>
+        /// <typeparam name="T">The wrapped task result type.</typeparam>
         private struct CompletionResult<T>
         {
+            /// <summary>
+            /// Initializes a completion result.
+            /// </summary>
+            /// <param name="completed">True when the task completed before the timeout.</param>
+            /// <param name="result">The task result or a default value.</param>
             public CompletionResult(bool completed, T result)
             {
                 Completed = completed;
                 Result = result;
             }
 
+            /// <summary>
+            /// Gets a value indicating whether the wrapped task completed in time.
+            /// </summary>
             public bool Completed { get; private set; }
+
+            /// <summary>
+            /// Gets the wrapped task result.
+            /// </summary>
             public T Result { get; private set; }
         }
     }

src/HostAvailabilityMonitor/Monitoring/ProbeResult.cs

@@ -2,43 +2,175 @@ using System;
 
 namespace HostAvailabilityMonitor.Monitoring
 {
+    /// <summary>
+    /// Identifies the endpoint probe strategy used for a target.
+    /// </summary>
     public enum TargetKind
     {
+        /// <summary>
+        /// The target type could not be resolved.
+        /// </summary>
         Unknown = 0,
+
+        /// <summary>
+        /// A UNC or SMB path target.
+        /// </summary>
         Unc = 1,
+
+        /// <summary>
+        /// An HTTP endpoint target.
+        /// </summary>
         Http = 2,
+
+        /// <summary>
+        /// An HTTPS endpoint target.
+        /// </summary>
         Https = 3,
+
+        /// <summary>
+        /// An SFTP endpoint target.
+        /// </summary>
         Sftp = 4,
+
+        /// <summary>
+        /// A generic TCP endpoint target.
+        /// </summary>
         Tcp = 5,
+
+        /// <summary>
+        /// An ICMP ping target.
+        /// </summary>
         Icmp = 6,
+
+        /// <summary>
+        /// A plain host target resolved through target options.
+        /// </summary>
         Host = 7,
+
+        /// <summary>
+        /// An FTP endpoint target.
+        /// </summary>
         Ftp = 8,
+
+        /// <summary>
+        /// A local or file URI target.
+        /// </summary>
         File = 9,
+
+        /// <summary>
+        /// An RDP TCP endpoint target.
+        /// </summary>
         Rdp = 10
     }
 
+    /// <summary>
+    /// Contains the result of probing one configured target.
+    /// </summary>
     public sealed class ProbeResult
     {
+        /// <summary>
+        /// Gets or sets the stable state key for the target.
+        /// </summary>
         public string StateKey { get; set; }
+
+        /// <summary>
+        /// Gets or sets the display name of the target.
+        /// </summary>
         public string Name { get; set; }
+
+        /// <summary>
+        /// Gets or sets the logical application name.
+        /// </summary>
         public string ApplicationName { get; set; }
+
+        /// <summary>
+        /// Gets or sets the endpoint that was probed.
+        /// </summary>
         public string Endpoint { get; set; }
+
+        /// <summary>
+        /// Gets or sets the resolved target kind.
+        /// </summary>
         public TargetKind Kind { get; set; }
+
+        /// <summary>
+        /// Gets or sets a value indicating whether the probe succeeded.
+        /// </summary>
         public bool IsSuccess { get; set; }
+
+        /// <summary>
+        /// Gets or sets a value indicating whether the target was intentionally skipped.
+        /// </summary>
         public bool IsSkipped { get; set; }
+
+        /// <summary>
+        /// Gets or sets the high-level status text.
+        /// </summary>
         public string StatusText { get; set; }
+
+        /// <summary>
+        /// Gets or sets the detailed probe result message.
+        /// </summary>
         public string Detail { get; set; }
+
+        /// <summary>
+        /// Gets or sets the resolved host name or address.
+        /// </summary>
         public string Host { get; set; }
+
+        /// <summary>
+        /// Gets or sets the resolved port, when applicable.
+        /// </summary>
         public int? Port { get; set; }
+
+        /// <summary>
+        /// Gets or sets the source that created the target.
+        /// </summary>
         public string Source { get; set; }
+
+        /// <summary>
+        /// Gets or sets the group label used in reports.
+        /// </summary>
         public string Group { get; set; }
+
+        /// <summary>
+        /// Gets or sets the target description.
+        /// </summary>
         public string Description { get; set; }
+
+        /// <summary>
+        /// Gets or sets the machine name for generated VM checks.
+        /// </summary>
         public string MachineName { get; set; }
+
+        /// <summary>
+        /// Gets or sets the check name for generated checks.
+        /// </summary>
         public string CheckName { get; set; }
+
+        /// <summary>
+        /// Gets or sets the HTTP status code returned by HTTP probes.
+        /// </summary>
         public int? HttpStatusCode { get; set; }
+
+        /// <summary>
+        /// Gets or sets the exception type observed during failed probes.
+        /// </summary>
         public string ErrorType { get; set; }
+
+        /// <summary>
+        /// Gets or sets the local start time of the probe.
+        /// </summary>
         public DateTimeOffset StartedAtLocal { get; set; }
+
+        /// <summary>
+        /// Gets or sets the local finish time of the probe.
+        /// </summary>
         public DateTimeOffset FinishedAtLocal { get; set; }
+
+        /// <summary>
+        /// Gets the elapsed probe duration.
+        /// </summary>
         public TimeSpan Duration
         {
             get { return FinishedAtLocal - StartedAtLocal; }

src/HostAvailabilityMonitor/Notifications/EmailNotifier.cs

@@ -12,12 +12,32 @@ using HostAvailabilityMonitor.State;
 
 namespace HostAvailabilityMonitor.Notifications
 {
+    /// <summary>
+    /// Sends failure, recovery and daily summary emails for monitor results.
+    /// </summary>
     public sealed class EmailNotifier
     {
+        /// <summary>
+        /// SMTP and notification settings.
+        /// </summary>
         private readonly EmailOptions _options;
+
+        /// <summary>
+        /// Monitor name written into subjects and message bodies.
+        /// </summary>
         private readonly string _monitorName;
+
+        /// <summary>
+        /// Environment name written into subjects and message bodies.
+        /// </summary>
         private readonly string _environmentName;
 
+        /// <summary>
+        /// Initializes a new email notifier.
+        /// </summary>
+        /// <param name="options">SMTP and notification options.</param>
+        /// <param name="monitorName">The monitor name for outgoing messages.</param>
+        /// <param name="environmentName">The environment name for outgoing messages.</param>
         public EmailNotifier(EmailOptions options, string monitorName, string environmentName)
         {
             _options = options ?? new EmailOptions();
@@ -25,11 +45,20 @@ namespace HostAvailabilityMonitor.Notifications
             _environmentName = string.IsNullOrWhiteSpace(environmentName) ? "Unspecified Environment" : environmentName.Trim();
         }
 
+        /// <summary>
+        /// Gets a value indicating whether email delivery is enabled.
+        /// </summary>
         public bool IsEnabled
         {
             get { return _options.Enabled; }
         }
 
+        /// <summary>
+        /// Determines whether a probe result should trigger a failure or recovery notification.
+        /// </summary>
+        /// <param name="result">The current probe result.</param>
+        /// <param name="previousState">The previous persisted state for the target.</param>
+        /// <returns>True when a notification should be sent.</returns>
         public bool ShouldNotify(ProbeResult result, TargetState previousState)
         {
             if (!IsEnabled || result == null)
@@ -72,6 +101,12 @@ namespace HostAvailabilityMonitor.Notifications
             return cooldownPassed;
         }
 
+        /// <summary>
+        /// Determines whether the daily summary should be sent on this run.
+        /// </summary>
+        /// <param name="metadata">The persisted monitor metadata.</param>
+        /// <param name="nowLocal">The current local server time.</param>
+        /// <returns>True when the daily summary should be sent.</returns>
         public bool ShouldSendDailySummary(MonitorStateMetadata metadata, DateTime nowLocal)
         {
             if (!IsEnabled || !_options.SendDailySummary)
@@ -89,6 +124,14 @@ namespace HostAvailabilityMonitor.Notifications
             return metadata == null || !string.Equals(metadata.LastDailySummarySentLocalDate, localDate, StringComparison.Ordinal);
         }
 
+        /// <summary>
+        /// Sends one notification email for the supplied failures and recoveries.
+        /// </summary>
+        /// <param name="failures">The failed probe results to include.</param>
+        /// <param name="recoveries">The recovered probe results to include.</param>
+        /// <param name="currentState">The current target state dictionary.</param>
+        /// <param name="cancellationToken">A token that can cancel SMTP delivery.</param>
+        /// <returns>A task that completes when delivery has finished.</returns>
         public async Task SendAsync(
             IReadOnlyCollection<ProbeResult> failures,
             IReadOnlyCollection<ProbeResult> recoveries,
@@ -112,6 +155,12 @@ namespace HostAvailabilityMonitor.Notifications
             await SendMailAsync(subject, body, cancellationToken).ConfigureAwait(false);
         }
 
+        /// <summary>
+        /// Sends the once-per-day status summary email.
+        /// </summary>
+        /// <param name="summary">The summary data to render.</param>
+        /// <param name="cancellationToken">A token that can cancel SMTP delivery.</param>
+        /// <returns>A task that completes when delivery has finished.</returns>
         public async Task SendDailySummaryAsync(DailySummaryEmailData summary, CancellationToken cancellationToken)
         {
             if (!IsEnabled || summary == null)
@@ -124,6 +173,13 @@ namespace HostAvailabilityMonitor.Notifications
             await SendMailAsync(subject, body, cancellationToken).ConfigureAwait(false);
         }
 
+        /// <summary>
+        /// Sends one SMTP email.
+        /// </summary>
+        /// <param name="subject">The email subject.</param>
+        /// <param name="body">The plain-text email body.</param>
+        /// <param name="cancellationToken">A token that can cancel SMTP delivery before sending starts.</param>
+        /// <returns>A task that completes when SMTP delivery has finished.</returns>
         private async Task SendMailAsync(string subject, string body, CancellationToken cancellationToken)
         {
             using (var message = new MailMessage())
@@ -161,6 +217,11 @@ namespace HostAvailabilityMonitor.Notifications
             }
         }
 
+        /// <summary>
+        /// Adds normalized recipient addresses to a mail address collection.
+        /// </summary>
+        /// <param name="collection">The destination mail address collection.</param>
+        /// <param name="recipients">The configured recipient strings.</param>
         private static void AddRecipients(MailAddressCollection collection, IEnumerable<string> recipients)
         {
             if (collection == null || recipients == null)
@@ -174,6 +235,12 @@ namespace HostAvailabilityMonitor.Notifications
             }
         }
 
+        /// <summary>
+        /// Detects a transition from previously down to currently up.
+        /// </summary>
+        /// <param name="result">The current probe result.</param>
+        /// <param name="previousState">The previous persisted state for the target.</param>
+        /// <returns>True when the result is a recovery transition.</returns>
         private static bool IsRecoveryTransition(ProbeResult result, TargetState previousState)
         {
             return result != null
@@ -182,6 +249,12 @@ namespace HostAvailabilityMonitor.Notifications
                 && !previousState.IsUp;
         }
 
+        /// <summary>
+        /// Builds the subject for failure and recovery notification emails.
+        /// </summary>
+        /// <param name="failureCount">The number of failures in the message.</param>
+        /// <param name="recoveryCount">The number of recoveries in the message.</param>
+        /// <returns>The notification subject.</returns>
         private string BuildSubject(int failureCount, int recoveryCount)
         {
             var prefix = string.IsNullOrWhiteSpace(_options.SubjectPrefix) ? "[HostAvailabilityMonitor]" : _options.SubjectPrefix.Trim();
@@ -200,6 +273,11 @@ namespace HostAvailabilityMonitor.Notifications
             return string.Format("{0} {1} {2} Endpoint(s) wieder erreichbar", prefix, envPart, recoveryCount);
         }
 
+        /// <summary>
+        /// Builds the subject for a daily summary email.
+        /// </summary>
+        /// <param name="summary">The summary data.</param>
+        /// <returns>The daily summary subject.</returns>
         private string BuildDailySummarySubject(DailySummaryEmailData summary)
         {
             var prefix = string.IsNullOrWhiteSpace(_options.SubjectPrefix) ? "[HostAvailabilityMonitor]" : _options.SubjectPrefix.Trim();
@@ -207,6 +285,13 @@ namespace HostAvailabilityMonitor.Notifications
             return string.Format("{0} {1} Tagesstatus {2:yyyy-MM-dd}", prefix, envPart, summary.GeneratedAtLocal.LocalDateTime.Date);
         }
 
+        /// <summary>
+        /// Builds the plain-text body for failure and recovery notifications.
+        /// </summary>
+        /// <param name="failures">The failed probe results to include.</param>
+        /// <param name="recoveries">The recovered probe results to include.</param>
+        /// <param name="currentState">The current target state dictionary.</param>
+        /// <returns>The email body.</returns>
         private string BuildBody(IReadOnlyCollection<ProbeResult> failures, IReadOnlyCollection<ProbeResult> recoveries, IDictionary<string, TargetState> currentState)
         {
             var sb = new StringBuilder();
@@ -239,6 +324,11 @@ namespace HostAvailabilityMonitor.Notifications
             return sb.ToString();
         }
 
+        /// <summary>
+        /// Builds the plain-text body for a daily summary email.
+        /// </summary>
+        /// <param name="summary">The summary data to render.</param>
+        /// <returns>The email body.</returns>
         private string BuildDailySummaryBody(DailySummaryEmailData summary)
         {
             var sb = new StringBuilder();
@@ -281,6 +371,13 @@ namespace HostAvailabilityMonitor.Notifications
             return sb.ToString();
         }
 
+        /// <summary>
+        /// Appends one probe result to an email body.
+        /// </summary>
+        /// <param name="sb">The message body builder.</param>
+        /// <param name="result">The result to append.</param>
+        /// <param name="currentState">The current target state dictionary.</param>
+        /// <param name="transitionText">The transition text to show.</param>
         private static void AppendResult(StringBuilder sb, ProbeResult result, IDictionary<string, TargetState> currentState, string transitionText)
         {
             sb.AppendLine("- Anwendung / Application: " + Safe(result.ApplicationName));
@@ -328,6 +425,11 @@ namespace HostAvailabilityMonitor.Notifications
             }
         }
 
+        /// <summary>
+        /// Appends a compact HIP VM network and RDP snapshot to the daily summary.
+        /// </summary>
+        /// <param name="sb">The message body builder.</param>
+        /// <param name="results">The current probe results.</param>
         private static void AppendHipVirtualMachineSnapshot(StringBuilder sb, IReadOnlyCollection<ProbeResult> results)
         {
             if (results == null)
@@ -371,6 +473,11 @@ namespace HostAvailabilityMonitor.Notifications
             }
         }
 
+        /// <summary>
+        /// Builds a grouping key for HIP VM snapshot rows.
+        /// </summary>
+        /// <param name="result">The probe result to key.</param>
+        /// <returns>The grouping key.</returns>
         private static string BuildVmSnapshotKey(ProbeResult result)
         {
             return string.Join("|", new[]
@@ -381,6 +488,11 @@ namespace HostAvailabilityMonitor.Notifications
             });
         }
 
+        /// <summary>
+        /// Formats one probe result as a compact status string.
+        /// </summary>
+        /// <param name="result">The result to format.</param>
+        /// <returns>A compact status string.</returns>
         private static string FormatCompactStatus(ProbeResult result)
         {
             if (result == null)
@@ -396,6 +508,11 @@ namespace HostAvailabilityMonitor.Notifications
             return (result.IsSuccess ? "UP" : "DOWN") + " - " + Safe(result.Detail);
         }
 
+        /// <summary>
+        /// Returns the first non-empty value from a sequence.
+        /// </summary>
+        /// <param name="values">The values to inspect.</param>
+        /// <returns>The first non-empty value, or an empty string.</returns>
         private static string FirstNonEmpty(IEnumerable<string> values)
         {
             if (values == null)
@@ -406,26 +523,85 @@ namespace HostAvailabilityMonitor.Notifications
             return values.FirstOrDefault(v => !string.IsNullOrWhiteSpace(v)) ?? string.Empty;
         }
 
+        /// <summary>
+        /// Converts null or whitespace values into a readable placeholder.
+        /// </summary>
+        /// <param name="value">The value to normalize.</param>
+        /// <returns>The original value or n/a.</returns>
         private static string Safe(string value)
         {
             return string.IsNullOrWhiteSpace(value) ? "n/a" : value;
         }
     }
 
+    /// <summary>
+    /// Contains all data required to render a daily status summary email.
+    /// </summary>
     public sealed class DailySummaryEmailData
     {
+        /// <summary>
+        /// Gets or sets the local timestamp when the summary is generated.
+        /// </summary>
         public DateTimeOffset GeneratedAtLocal { get; set; }
+
+        /// <summary>
+        /// Gets or sets the local start timestamp of the summary window.
+        /// </summary>
         public DateTimeOffset WindowStartLocal { get; set; }
+
+        /// <summary>
+        /// Gets or sets today's total probe count from the rolling log.
+        /// </summary>
         public int ProbesTodayTotal { get; set; }
+
+        /// <summary>
+        /// Gets or sets today's successful probe count from the rolling log.
+        /// </summary>
         public int ProbesTodaySuccess { get; set; }
+
+        /// <summary>
+        /// Gets or sets today's failed probe count from the rolling log.
+        /// </summary>
         public int ProbesTodayFailure { get; set; }
+
+        /// <summary>
+        /// Gets or sets today's skipped probe count from the rolling log.
+        /// </summary>
         public int ProbesTodaySkipped { get; set; }
+
+        /// <summary>
+        /// Gets or sets the number of targets in the latest run.
+        /// </summary>
         public int CurrentTargetsTotal { get; set; }
+
+        /// <summary>
+        /// Gets or sets the number of currently reachable targets.
+        /// </summary>
         public int CurrentTargetsUp { get; set; }
+
+        /// <summary>
+        /// Gets or sets the number of currently unreachable targets.
+        /// </summary>
         public int CurrentTargetsDown { get; set; }
+
+        /// <summary>
+        /// Gets or sets the number of currently skipped targets.
+        /// </summary>
         public int CurrentTargetsSkipped { get; set; }
+
+        /// <summary>
+        /// Gets or sets the currently failed probe results.
+        /// </summary>
         public List<ProbeResult> CurrentFailures { get; set; } = new List<ProbeResult>();
+
+        /// <summary>
+        /// Gets or sets all current probe results.
+        /// </summary>
         public List<ProbeResult> CurrentResults { get; set; } = new List<ProbeResult>();
+
+        /// <summary>
+        /// Gets or sets the current target state dictionary.
+        /// </summary>
         public IDictionary<string, TargetState> CurrentState { get; set; } = new Dictionary<string, TargetState>(StringComparer.OrdinalIgnoreCase);
     }
 }

src/HostAvailabilityMonitor/Program.cs

@@ -12,44 +12,67 @@ using HostAvailabilityMonitor.State;
 
 namespace HostAvailabilityMonitor
 {
+    /// <summary>
+    /// Console entry point and orchestration workflow for one monitor run.
+    /// </summary>
     internal static class Program
     {
+        /// <summary>
+        /// Starts the monitor synchronously for the console host.
+        /// </summary>
+        /// <param name="args">Optional command-line arguments. The first argument may be the configuration path.</param>
+        /// <returns>The process exit code.</returns>
         private static int Main(string[] args)
         {
             return MainAsync(args).GetAwaiter().GetResult();
         }
 
+        /// <summary>
+        /// Executes one complete monitor run.
+        /// </summary>
+        /// <param name="args">Optional command-line arguments. The first argument may be the configuration path.</param>
+        /// <returns>The process exit code.</returns>
         private static async Task<int> MainAsync(string[] args)
         {
             FileLogger logger = null;
             WindowsEventLogger eventLogger = null;
             var nonZeroExitCodeOnExecutionError = true;
+            string baseDirectory = null;
+            string configPath = null;
 
             try
             {
-                var baseDirectory = AppDomain.CurrentDomain.BaseDirectory;
-                var configPath = args != null && args.Length > 0 && !string.IsNullOrWhiteSpace(args[0])
+                baseDirectory = AppDomain.CurrentDomain.BaseDirectory;
+                configPath = args != null && args.Length > 0 && !string.IsNullOrWhiteSpace(args[0])
                     ? args[0]
                     : Path.Combine(baseDirectory, "appsettings.json");
                 var fullConfigPath = Path.GetFullPath(configPath);
 
+                WriteConsoleBanner("Host Availability Monitor", fullConfigPath);
+                WriteConsoleInfo("Lade Monitor-Konfiguration...");
+
                 var config = MonitorConfiguration.Load(configPath);
                 config.Validate();
                 nonZeroExitCodeOnExecutionError = config.Runtime.NonZeroExitCodeOnExecutionError;
+                WriteConsoleInfo("Konfiguration geladen. Umgebung=" + config.EnvironmentName + ".");
 
                 var logDirectory = ResolvePath(baseDirectory, config.Logging.LogDirectory);
                 var stateDirectory = ResolvePath(baseDirectory, config.Runtime.StateDirectory);
                 var stateFilePath = Path.Combine(stateDirectory, "monitor-state.json");
 
+                WriteConsoleInfo("Initialisiere Dateilog: " + BuildLogFilePreview(logDirectory, config.Logging.FilePrefix));
                 logger = new FileLogger(logDirectory, config.Logging.FilePrefix, config.Logging.RetentionDays, config.ApplicationName, config.EnvironmentName);
                 logger.CleanupOldFiles();
                 logger.Info(config.ApplicationName + " gestartet. Umgebung=" + config.EnvironmentName + ", Server=" + Environment.MachineName + ".");
                 logger.Info("Konfiguration geladen: " + fullConfigPath);
+                logger.Info("Statusdatei: " + stateFilePath);
 
+                WriteConsoleInfo("Initialisiere Windows Event Log. Quelle=" + config.EventLog.Source + ", Log=" + config.EventLog.LogName + ", Aktiv=" + config.EventLog.Enabled + ".");
                 eventLogger = new WindowsEventLogger(config.EventLog, logger);
                 eventLogger.TryInitialize();
                 eventLogger.Info(config.ApplicationName + " gestartet. Umgebung=" + config.EnvironmentName + ", Server=" + Environment.MachineName + ".", 1000);
 
+                WriteConsoleInfo("Lade Statusdatei: " + stateFilePath);
                 Directory.CreateDirectory(stateDirectory);
                 var stateStore = new MonitorStateStore(stateFilePath);
                 MonitorStateDocument stateDocument;
@@ -69,15 +92,23 @@ namespace HostAvailabilityMonitor
                 var currentState = new Dictionary<string, TargetState>(previousState, StringComparer.OrdinalIgnoreCase);
                 var probeService = new EndpointProbeService(config.Runtime);
                 var enabledTargets = BuildEnabledTargets(config, fullConfigPath, baseDirectory, logger);
+                logger.Info("Aktivierte Targets vorbereitet. Anzahl=" + enabledTargets.Count + ", MaxConcurrency=" + config.Runtime.MaxConcurrency + ".");
+                eventLogger.Info("Monitor-Targets vorbereitet. Umgebung=" + config.EnvironmentName + ", AktivierteTargets=" + enabledTargets.Count + ", MaxConcurrency=" + config.Runtime.MaxConcurrency + ".", 1002);
+                WriteConsoleInfo("Aktivierte Targets vorbereitet: " + enabledTargets.Count + ".");
 
                 if (enabledTargets.Count == 0)
                 {
                     logger.Warn("Es sind keine aktivierten Targets vorhanden. Der Lauf endet ohne Checks.");
                     eventLogger.Summary(config.ApplicationName + " ausgeführt, aber es waren keine aktivierten Targets vorhanden. Umgebung=" + config.EnvironmentName + ".", false);
+                    WriteConsoleWarn("Keine aktivierten Targets vorhanden. Der Lauf endet ohne Checks.");
                     return 0;
                 }
 
+                WriteConsoleInfo("Starte Endpoint-Checks...");
+                logger.Info("Endpoint-Checks starten. Targets=" + enabledTargets.Count + ".");
+                eventLogger.Info("Endpoint-Checks gestartet. Umgebung=" + config.EnvironmentName + ", Targets=" + enabledTargets.Count + ".", 1003);
                 var results = await ExecuteChecksAsync(enabledTargets, probeService, config.Runtime.MaxConcurrency).ConfigureAwait(false);
+                WriteConsoleInfo("Endpoint-Checks abgeschlossen. Ergebnisse=" + results.Count + ".");
 
                 foreach (var result in results.OrderBy(r => r.ApplicationName, StringComparer.OrdinalIgnoreCase).ThenBy(r => r.Name, StringComparer.OrdinalIgnoreCase))
                 {
@@ -168,6 +199,9 @@ namespace HostAvailabilityMonitor
 
                 await TrySendDailySummaryAsync(config, notifier, stateDocument, currentState, results, logDirectory, logger, eventLogger).ConfigureAwait(false);
                 stateStore.Save(stateDocument);
+                logger.Info("Statusdatei gespeichert: " + stateFilePath);
+                eventLogger.Info("Monitor-Status gespeichert. Umgebung=" + config.EnvironmentName + ", Pfad=" + stateFilePath + ".", 1004);
+                WriteConsoleInfo("Statusdatei gespeichert: " + stateFilePath);
 
                 var total = results.Count(r => !r.IsSkipped);
                 var ok = results.Count(r => r.IsSuccess);
@@ -176,14 +210,22 @@ namespace HostAvailabilityMonitor
                 var summary = config.ApplicationName + " Lauf beendet. Umgebung=" + config.EnvironmentName + ", Gesamt=" + total + ", Erfolgreich=" + ok + ", Fehlgeschlagen=" + failed + ", Uebersprungen=" + skipped + ".";
                 logger.Info(summary);
                 eventLogger.Summary(summary, failed > 0);
+                WriteConsoleInfo(summary);
 
                 return failed > 0 && config.Runtime.NonZeroExitCodeOnAnyFailure ? 2 : 0;
             }
             catch (Exception ex)
             {
+                WriteConsoleFatal("Monitorlauf fehlgeschlagen.", configPath, ex);
+
                 if (logger != null)
                 {
                     logger.Error("Fataler Fehler: " + ex.GetType().Name + ": " + ex.Message);
+                    logger.Error("Details: " + ex);
+                }
+                else
+                {
+                    TryWriteFallbackFailureLog(baseDirectory, configPath, ex);
                 }
 
                 if (eventLogger != null)
@@ -195,6 +237,13 @@ namespace HostAvailabilityMonitor
             }
         }
 
+        /// <summary>
+        /// Executes endpoint checks with the configured concurrency limit.
+        /// </summary>
+        /// <param name="targets">The enabled targets to probe.</param>
+        /// <param name="probeService">The endpoint probe service.</param>
+        /// <param name="maxConcurrency">The maximum number of concurrent probes.</param>
+        /// <returns>The collected probe results.</returns>
         private static async Task<List<ProbeResult>> ExecuteChecksAsync(IReadOnlyCollection<TargetOptions> targets, EndpointProbeService probeService, int maxConcurrency)
         {
             var results = new List<ProbeResult>();
@@ -220,6 +269,14 @@ namespace HostAvailabilityMonitor
             return results;
         }
 
+        /// <summary>
+        /// Builds the enabled target list from static configuration and optional HIP VM configuration.
+        /// </summary>
+        /// <param name="config">The monitor configuration.</param>
+        /// <param name="configPath">The full monitor configuration path.</param>
+        /// <param name="baseDirectory">The application base directory.</param>
+        /// <param name="logger">The file logger for operational messages.</param>
+        /// <returns>The enabled targets to probe.</returns>
         private static List<TargetOptions> BuildEnabledTargets(MonitorConfiguration config, string configPath, string baseDirectory, FileLogger logger)
         {
             var targets = config.Targets == null
@@ -242,6 +299,13 @@ namespace HostAvailabilityMonitor
             return targets;
         }
 
+        /// <summary>
+        /// Creates monitor targets for enabled HIP virtual machines.
+        /// </summary>
+        /// <param name="vmConfig">The HIP virtual machine configuration.</param>
+        /// <param name="options">The HIP virtual machine monitor options.</param>
+        /// <param name="logger">The file logger for skipped VM messages.</param>
+        /// <returns>The generated monitor targets.</returns>
         private static List<TargetOptions> CreateHipVirtualMachineTargets(HipVirtualMachineConfiguration vmConfig, HipVirtualMachineOptions options, FileLogger logger)
         {
             var targets = new List<TargetOptions>();
@@ -297,6 +361,18 @@ namespace HostAvailabilityMonitor
             return targets;
         }
 
+        /// <summary>
+        /// Creates one generated target for a HIP virtual machine check.
+        /// </summary>
+        /// <param name="vm">The source HIP virtual machine.</param>
+        /// <param name="machineName">The display machine name.</param>
+        /// <param name="applicationName">The application name assigned to generated targets.</param>
+        /// <param name="checkName">The technical check name.</param>
+        /// <param name="displayCheckName">The display check name.</param>
+        /// <param name="endpoint">The generated endpoint.</param>
+        /// <param name="port">The generated port, when applicable.</param>
+        /// <param name="timeoutSeconds">The generated target timeout.</param>
+        /// <returns>The generated target.</returns>
         private static TargetOptions CreateHipVirtualMachineTarget(
             HipVirtualMachine vm,
             string machineName,
@@ -323,6 +399,13 @@ namespace HostAvailabilityMonitor
             };
         }
 
+        /// <summary>
+        /// Resolves a configuration-relative path against the configuration directory first, then the application base directory.
+        /// </summary>
+        /// <param name="configPath">The main configuration path.</param>
+        /// <param name="baseDirectory">The application base directory.</param>
+        /// <param name="configuredPath">The configured relative or absolute path.</param>
+        /// <returns>The resolved path.</returns>
         private static string ResolveConfigurationPath(string configPath, string baseDirectory, string configuredPath)
         {
             if (Path.IsPathRooted(configuredPath))
@@ -340,6 +423,18 @@ namespace HostAvailabilityMonitor
             return Path.GetFullPath(Path.Combine(baseDirectory, configuredPath));
         }
 
+        /// <summary>
+        /// Sends the daily summary email when it is due and updates state metadata only after successful delivery.
+        /// </summary>
+        /// <param name="config">The monitor configuration.</param>
+        /// <param name="notifier">The email notifier.</param>
+        /// <param name="stateDocument">The mutable state document.</param>
+        /// <param name="currentState">The current target state dictionary.</param>
+        /// <param name="results">The latest probe results.</param>
+        /// <param name="logDirectory">The log directory used to calculate daily counters.</param>
+        /// <param name="logger">The file logger.</param>
+        /// <param name="eventLogger">The Event Log writer.</param>
+        /// <returns>A task that completes when the summary check has finished.</returns>
         private static async Task TrySendDailySummaryAsync(
             MonitorConfiguration config,
             EmailNotifier notifier,
@@ -395,6 +490,14 @@ namespace HostAvailabilityMonitor
             }
         }
 
+        /// <summary>
+        /// Reads today's probe counters from the current rolling log file.
+        /// </summary>
+        /// <param name="logDirectory">The log directory.</param>
+        /// <param name="filePrefix">The monitor log file prefix.</param>
+        /// <param name="nowLocal">The current local server time.</param>
+        /// <param name="logger">The file logger used for fallback warnings.</param>
+        /// <returns>The counters found in today's log file.</returns>
         private static ProbeLogCounters ReadTodayProbeCounters(string logDirectory, string filePrefix, DateTime nowLocal, FileLogger logger)
         {
             var counters = new ProbeLogCounters();
@@ -435,6 +538,12 @@ namespace HostAvailabilityMonitor
             return counters;
         }
 
+        /// <summary>
+        /// Updates persisted state for one non-skipped probe result.
+        /// </summary>
+        /// <param name="currentState">The mutable current state dictionary.</param>
+        /// <param name="result">The latest probe result.</param>
+        /// <param name="previousState">The previously persisted target state.</param>
         private static void UpdateState(Dictionary<string, TargetState> currentState, ProbeResult result, TargetState previousState)
         {
             var nowUtc = DateTime.UtcNow;
@@ -477,6 +586,12 @@ namespace HostAvailabilityMonitor
             currentState[result.StateKey] = state;
         }
 
+        /// <summary>
+        /// Resolves a configured path against the application base directory.
+        /// </summary>
+        /// <param name="baseDirectory">The application base directory.</param>
+        /// <param name="configuredPath">The configured relative or absolute path.</param>
+        /// <returns>The resolved path.</returns>
         private static string ResolvePath(string baseDirectory, string configuredPath)
         {
             if (Path.IsPathRooted(configuredPath))
@@ -487,6 +602,12 @@ namespace HostAvailabilityMonitor
             return Path.GetFullPath(Path.Combine(baseDirectory, configuredPath));
         }
 
+        /// <summary>
+        /// Builds a structured Event Log message for one probe result.
+        /// </summary>
+        /// <param name="config">The monitor configuration.</param>
+        /// <param name="result">The probe result.</param>
+        /// <returns>The formatted Event Log message.</returns>
         private static string BuildEventMessage(MonitorConfiguration config, ProbeResult result)
         {
             return string.Format(
@@ -504,10 +625,122 @@ namespace HostAvailabilityMonitor
                 result.Detail);
         }
 
+        /// <summary>
+        /// Writes the initial console banner before configuration and file logging are available.
+        /// </summary>
+        /// <param name="title">The program title.</param>
+        /// <param name="configPath">The resolved configuration path.</param>
+        private static void WriteConsoleBanner(string title, string configPath)
+        {
+            TryWriteConsoleLine(Console.Out, "============================================================");
+            TryWriteConsoleLine(Console.Out, title);
+            TryWriteConsoleLine(Console.Out, "Server: " + Environment.MachineName);
+            TryWriteConsoleLine(Console.Out, "Start:  " + DateTimeOffset.Now.ToString("yyyy-MM-dd HH:mm:ss zzz"));
+            TryWriteConsoleLine(Console.Out, "Config: " + (configPath ?? "(nicht aufgeloest)"));
+            TryWriteConsoleLine(Console.Out, "============================================================");
+        }
+
+        /// <summary>
+        /// Writes a console information message.
+        /// </summary>
+        /// <param name="message">The message to write.</param>
+        private static void WriteConsoleInfo(string message)
+        {
+            TryWriteConsoleLine(Console.Out, "[INFO] " + message);
+        }
+
+        /// <summary>
+        /// Writes a console warning message.
+        /// </summary>
+        /// <param name="message">The message to write.</param>
+        private static void WriteConsoleWarn(string message)
+        {
+            TryWriteConsoleLine(Console.Out, "[WARN] " + message);
+        }
+
+        /// <summary>
+        /// Writes a fatal console error with actionable context.
+        /// </summary>
+        /// <param name="message">The user-facing failure message.</param>
+        /// <param name="configPath">The configuration path used for the run.</param>
+        /// <param name="exception">The exception that ended the run.</param>
+        private static void WriteConsoleFatal(string message, string configPath, Exception exception)
+        {
+            TryWriteConsoleLine(Console.Error, "[ERROR] " + message);
+            TryWriteConsoleLine(Console.Error, "[ERROR] Konfiguration: " + (configPath ?? "(nicht aufgeloest)"));
+            TryWriteConsoleLine(Console.Error, "[ERROR] Ursache: " + exception.GetType().Name + ": " + exception.Message);
+            TryWriteConsoleLine(Console.Error, "[ERROR] Details: " + exception);
+        }
+
+        /// <summary>
+        /// Writes one line to a console writer and ignores secondary console failures.
+        /// </summary>
+        /// <param name="writer">The console writer.</param>
+        /// <param name="message">The line to write.</param>
+        private static void TryWriteConsoleLine(TextWriter writer, string message)
+        {
+            try
+            {
+                writer.WriteLine(message);
+            }
+            catch
+            {
+            }
+        }
+
+        /// <summary>
+        /// Writes a fallback fatal log when configured logging could not be initialized.
+        /// </summary>
+        /// <param name="baseDirectory">The application base directory.</param>
+        /// <param name="configPath">The configuration path used for the run.</param>
+        /// <param name="exception">The exception that ended the run.</param>
+        private static void TryWriteFallbackFailureLog(string baseDirectory, string configPath, Exception exception)
+        {
+            try
+            {
+                var directory = ResolvePath(baseDirectory ?? AppDomain.CurrentDomain.BaseDirectory, "logs");
+                var fallbackLogger = new FileLogger(directory, "host-availability-monitor-startup", 5, "HostAvailabilityMonitor", "Startup");
+                fallbackLogger.Error("Monitor konnte nicht gestartet werden. Konfiguration=" + (configPath ?? "(nicht aufgeloest)") + ". Fehler=" + exception.GetType().Name + ": " + exception.Message);
+                fallbackLogger.Error("Details: " + exception);
+                WriteConsoleInfo("Fallback-Log geschrieben: " + BuildLogFilePreview(directory, "host-availability-monitor-startup"));
+            }
+            catch (Exception fallbackEx)
+            {
+                TryWriteConsoleLine(Console.Error, "[ERROR] Fallback-Log konnte nicht geschrieben werden: " + fallbackEx.GetType().Name + ": " + fallbackEx.Message);
+            }
+        }
+
+        /// <summary>
+        /// Builds the expected daily log file path for console diagnostics.
+        /// </summary>
+        /// <param name="directory">The log directory.</param>
+        /// <param name="filePrefix">The rolling file prefix.</param>
+        /// <returns>The expected log file path for the current local date.</returns>
+        private static string BuildLogFilePreview(string directory, string filePrefix)
+        {
+            var safeDirectory = string.IsNullOrWhiteSpace(directory) ? AppDomain.CurrentDomain.BaseDirectory : directory;
+            var safePrefix = string.IsNullOrWhiteSpace(filePrefix) ? "host-availability-monitor" : filePrefix;
+            return Path.Combine(safeDirectory, safePrefix + "-" + DateTime.Now.ToString("yyyy-MM-dd") + ".log");
+        }
+
+        /// <summary>
+        /// Holds daily probe counters parsed from the rolling log.
+        /// </summary>
         private sealed class ProbeLogCounters
         {
+            /// <summary>
+            /// Gets or sets today's successful probe count.
+            /// </summary>
             public int SuccessCount { get; set; }
+
+            /// <summary>
+            /// Gets or sets today's failed probe count.
+            /// </summary>
             public int FailureCount { get; set; }
+
+            /// <summary>
+            /// Gets or sets today's skipped probe count.
+            /// </summary>
             public int SkipCount { get; set; }
         }
     }

src/HostAvailabilityMonitor/Properties/AssemblyInfo.cs

@@ -1,6 +1,7 @@
 using System.Reflection;
 using System.Runtime.InteropServices;
 
+// Assembly metadata for the HostAvailabilityMonitor console application.
 [assembly: AssemblyTitle("HostAvailabilityMonitor")]
 [assembly: AssemblyDescription("Windows Server 2019 kompatibler Host Availability Monitor auf .NET Framework 4.7.2")]
 [assembly: AssemblyConfiguration("")]

src/HostAvailabilityMonitor/State/MonitorStateStore.cs

@@ -5,15 +5,29 @@ using System.Web.Script.Serialization;
 
 namespace HostAvailabilityMonitor.State
 {
+    /// <summary>
+    /// Loads and saves the persisted monitor state file.
+    /// </summary>
     public sealed class MonitorStateStore
     {
+        /// <summary>
+        /// Full path to the JSON state file.
+        /// </summary>
         private readonly string _filePath;
 
+        /// <summary>
+        /// Initializes a new state store.
+        /// </summary>
+        /// <param name="filePath">The state JSON file path.</param>
         public MonitorStateStore(string filePath)
         {
             _filePath = filePath;
         }
 
+        /// <summary>
+        /// Loads the current state document and supports the legacy dictionary-only format.
+        /// </summary>
+        /// <returns>The loaded and normalized state document.</returns>
         public MonitorStateDocument LoadDocument()
         {
             if (!File.Exists(_filePath))
@@ -54,11 +68,19 @@ namespace HostAvailabilityMonitor.State
             }
         }
 
+        /// <summary>
+        /// Loads only the target state dictionary.
+        /// </summary>
+        /// <returns>The target states keyed by target state key.</returns>
         public Dictionary<string, TargetState> Load()
         {
             return LoadDocument().TargetStates;
         }
 
+        /// <summary>
+        /// Saves a complete monitor state document atomically.
+        /// </summary>
+        /// <param name="document">The document to persist.</param>
         public void Save(MonitorStateDocument document)
         {
             var directory = Path.GetDirectoryName(_filePath);
@@ -90,6 +112,10 @@ namespace HostAvailabilityMonitor.State
             }
         }
 
+        /// <summary>
+        /// Saves a target state dictionary using an empty metadata object.
+        /// </summary>
+        /// <param name="states">The target states to persist.</param>
         public void Save(Dictionary<string, TargetState> states)
         {
             Save(new MonitorStateDocument
@@ -101,6 +127,11 @@ namespace HostAvailabilityMonitor.State
             });
         }
 
+        /// <summary>
+        /// Ensures that state document collections and metadata are initialized.
+        /// </summary>
+        /// <param name="document">The document to normalize.</param>
+        /// <returns>The normalized document.</returns>
         private static MonitorStateDocument Normalize(MonitorStateDocument document)
         {
             if (document == null)
@@ -116,24 +147,66 @@ namespace HostAvailabilityMonitor.State
         }
     }
 
+    /// <summary>
+    /// Root object persisted in the monitor state file.
+    /// </summary>
     public sealed class MonitorStateDocument
     {
+        /// <summary>
+        /// Gets or sets target states keyed by target state key.
+        /// </summary>
         public Dictionary<string, TargetState> TargetStates { get; set; } = new Dictionary<string, TargetState>(StringComparer.OrdinalIgnoreCase);
+
+        /// <summary>
+        /// Gets or sets state metadata that is not tied to one target.
+        /// </summary>
         public MonitorStateMetadata Metadata { get; set; } = new MonitorStateMetadata();
     }
 
+    /// <summary>
+    /// Contains monitor state metadata shared across targets.
+    /// </summary>
     public sealed class MonitorStateMetadata
     {
+        /// <summary>
+        /// Gets or sets the local date for the most recent successfully sent daily summary email.
+        /// </summary>
         public string LastDailySummarySentLocalDate { get; set; } = string.Empty;
     }
 
+    /// <summary>
+    /// Persists the last known status and notification metadata for one target.
+    /// </summary>
     public sealed class TargetState
     {
+        /// <summary>
+        /// Gets or sets whether the target was up during the most recent non-skipped probe.
+        /// </summary>
         public bool IsUp { get; set; }
+
+        /// <summary>
+        /// Gets or sets the number of consecutive failed probes.
+        /// </summary>
         public int ConsecutiveFailures { get; set; }
+
+        /// <summary>
+        /// Gets or sets the UTC time of the most recent check.
+        /// </summary>
         public DateTime LastCheckedUtc { get; set; }
+
+        /// <summary>
+        /// Gets or sets the UTC time when the target last changed between up and down.
+        /// </summary>
         public DateTime LastChangedUtc { get; set; }
+
+        /// <summary>
+        /// Gets or sets the UTC time when the most recent notification was sent.
+        /// </summary>
         public DateTime? LastNotificationUtc { get; set; }
+
+        /// <summary>
+        /// Gets or sets the most recent probe detail text.
+        /// </summary>
         public string LastDetail { get; set; } = string.Empty;
     }
 }