feat: ship agent-first mission control v0.2.57

backend/Observability/NexusTelemetry.cs

@@ -0,0 +1,37 @@
+using System.Diagnostics;
+using System.Diagnostics.Metrics;
+
+namespace Nexus.Api.Observability;
+
+/// <summary>
+/// Low-cardinality diagnostics for the Nexus control plane. Content, prompts,
+/// tool arguments, entity names, credentials and caller-provided identifiers
+/// must never be recorded here.
+/// </summary>
+public static class NexusTelemetry
+{
+    public const string SourceName = "Nexus.Api";
+    public static readonly ActivitySource ActivitySource = new(SourceName);
+    public static readonly Meter Meter = new(SourceName);
+
+    public static readonly Histogram<double> BrowserDuration =
+        Meter.CreateHistogram<double>("nexus.browser.duration", unit: "ms");
+    public static readonly Histogram<double> BrowserScore =
+        Meter.CreateHistogram<double>("nexus.browser.score", unit: "1");
+    public static readonly Histogram<double> TaskBoardDuration =
+        Meter.CreateHistogram<double>("nexus.task.board.duration", unit: "ms");
+    public static readonly Histogram<long> TaskBoardPayload =
+        Meter.CreateHistogram<long>("nexus.task.board.payload", unit: "By");
+    public static readonly Counter<long> SseResyncs =
+        Meter.CreateCounter<long>("nexus.sse.resyncs");
+    public static readonly UpDownCounter<long> SseSubscribers =
+        Meter.CreateUpDownCounter<long>("nexus.sse.subscribers");
+    public static readonly Histogram<double> GatewayRpcDuration =
+        Meter.CreateHistogram<double>("nexus.gateway.rpc.duration", unit: "ms");
+    public static readonly UpDownCounter<long> OutboxBacklog =
+        Meter.CreateUpDownCounter<long>("nexus.outbox.backlog");
+    public static readonly Counter<long> OutboxPublished =
+        Meter.CreateCounter<long>("nexus.outbox.published");
+    public static readonly Histogram<double> AgentProvisionDuration =
+        Meter.CreateHistogram<double>("nexus.agent.provision.duration", unit: "ms");
+}