Include channel and subchannel info in Observability outgoing request header

packages/agents-a365-observability/src/tracing/exporter/Agent365Exporter.ts

@@ -7,7 +7,7 @@ import { ExportResult,ExportResultCode } from '@opentelemetry/core';
 import { ReadableSpan, SpanExporter } from '@opentelemetry/sdk-trace-base';
 
 import { PowerPlatformApiDiscovery, ClusterCategory } from '@microsoft/agents-a365-runtime';
-import { partitionByIdentity, parseIdentityKey, hexTraceId, hexSpanId, kindName, statusName } from './utils';
+import { buildAdditionalHttpRequestHeadersFromSpans, partitionByIdentity, parseIdentityKey, hexTraceId, hexSpanId, kindName, statusName } from './utils';
 import logger, { formatError } from '../../utils/logging';
 import { Agent365ExporterOptions } from './Agent365ExporterOptions';
 import { useCustomDomainForObservability, resolveAgent365Endpoint } from '../util';
@@ -163,6 +163,7 @@ export class Agent365Exporter implements SpanExporter {
       'content-type': 'application/json'
     };
 
+    Object.assign(headers, buildAdditionalHttpRequestHeadersFromSpans(spans));
     if (!this.options.tokenResolver) {
       logger.error('[Agent365Exporter] tokenResolver is undefined, skip exporting');
       return;

packages/agents-a365-observability/src/tracing/exporter/utils.ts

@@ -78,6 +78,40 @@ export function statusName(code: SpanStatusCode): string {
   }
 }
 
+/**
+ * Build additional HTTP request headers from span attributes.
+ *
+ * Extracts channel metadata when present on any of the provided spans:
+ * - `x-ms-channel-id` is sourced from `GEN_AI_EXECUTION_SOURCE_NAME_KEY`.
+ * - `x-ms-subchannel-id` is sourced from `GEN_AI_EXECUTION_SOURCE_DESCRIPTION_KEY`.
+ */
+export function buildAdditionalHttpRequestHeadersFromSpans(
+  spans: ReadableSpan[]
+): Record<string, string> {
+  const headers: Record<string, string> = {};
+
+  // Find the first span that has channel metadata
+  for (const span of spans) {
+    const attrs = span.attributes || {};
+    const channelId = asStr(attrs[OpenTelemetryConstants.GEN_AI_EXECUTION_SOURCE_NAME_KEY]);
+    const subchannelId = asStr(attrs[OpenTelemetryConstants.GEN_AI_EXECUTION_SOURCE_DESCRIPTION_KEY]);
+
+    if (channelId) {
+      headers['x-ms-channel-id'] = channelId;
+    }
+    if (subchannelId) {
+      headers['x-ms-subchannel-id'] = subchannelId;
+    }
+
+    // If both are set, we can stop early
+    if (headers['x-ms-channel-id'] && headers['x-ms-subchannel-id']) {
+      break;
+    }
+  }
+
+  return headers;
+}
+
 /**
  * Partition spans by (tenantId, agentId) identity pairs
  */

tests/observability/core/agent365-exporter.test.ts

@@ -164,4 +164,32 @@ describe('Agent365Exporter', () => {
     // Intentionally omit tokenResolver
     expect(() => new Agent365Exporter(opts)).toThrow(/tokenResolver must be provided/);
   });
+
+  it('adds channel headers from span attributes', async () => {
+    mockFetchSequence([200]);
+    const token = 'tok-headers';
+    const opts = new Agent365ExporterOptions();
+    opts.clusterCategory = 'prod';
+    opts.tokenResolver = () => token;
+    const exporter = new Agent365Exporter(opts);
+
+    const spans = [
+      makeSpan({
+        [OpenTelemetryConstants.TENANT_ID_KEY]: tenantId,
+        [OpenTelemetryConstants.GEN_AI_AGENT_ID_KEY]: agentId,
+        [OpenTelemetryConstants.GEN_AI_EXECUTION_SOURCE_NAME_KEY]: 'chat',
+        [OpenTelemetryConstants.GEN_AI_EXECUTION_SOURCE_DESCRIPTION_KEY]: 'thread-123'
+      })
+    ];
+
+    const callback = jest.fn();
+    await exporter.export(spans, callback);
+    expect(callback).toHaveBeenCalledWith({ code: ExportResultCode.SUCCESS });
+
+    const fetchCalls = (global.fetch as unknown as { mock: { calls: unknown[][] } }).mock.calls;
+    expect(fetchCalls.length).toBe(1);
+    const headersArg = (fetchCalls[0][1] as { headers: Record<string, string> }).headers;
+    expect(headersArg['x-ms-channel-id']).toBe('chat');
+    expect(headersArg['x-ms-subchannel-id']).toBe('thread-123');
+  });
 });