diff --git a/actions/setup/js/generate_observability_summary.cjs b/actions/setup/js/generate_observability_summary.cjs
index e28cd13d65c..b9ab440f927 100644
--- a/actions/setup/js/generate_observability_summary.cjs
+++ b/actions/setup/js/generate_observability_summary.cjs
@@ -60,7 +60,7 @@ function collectObservabilityData() {
   const agentOutput = readJSONIfExists(AGENT_OUTPUT_PATH) || { items: [], errors: [] };
   const items = Array.isArray(agentOutput.items) ? agentOutput.items : [];
   const errors = Array.isArray(agentOutput.errors) ? agentOutput.errors : [];
-  const traceId = awInfo.context && typeof awInfo.context.workflow_call_id === "string" ? awInfo.context.workflow_call_id : "";
+  const traceId = awInfo.context ? awInfo.context.otel_trace_id || awInfo.context.workflow_call_id || "" : "";
 
   return {
     workflowName: awInfo.workflow_name || "",
diff --git a/actions/setup/js/generate_observability_summary.test.cjs b/actions/setup/js/generate_observability_summary.test.cjs
index b3029b78758..51217610506 100644
--- a/actions/setup/js/generate_observability_summary.test.cjs
+++ b/actions/setup/js/generate_observability_summary.test.cjs
@@ -38,7 +38,7 @@ describe("generate_observability_summary.cjs", () => {
         engine_id: "copilot",
         staged: false,
         firewall_enabled: true,
-        context: { workflow_call_id: "trace-123" },
+        context: { workflow_call_id: "12345678901-1", otel_trace_id: "a3f2c8d1e4b7091f6a5c2e3d8f401b72" },
       })
     );
     fs.writeFileSync(
@@ -57,7 +57,8 @@ describe("generate_observability_summary.cjs", () => {
     expect(summary).toContain("<summary>Observability</summary>");
     expect(summary).toContain("- **workflow**: triage-workflow");
     expect(summary).toContain("- **engine**: copilot");
-    expect(summary).toContain("- **trace id**: trace-123");
+    expect(summary).toContain("- **trace id**: a3f2c8d1e4b7091f6a5c2e3d8f401b72");
+    expect(summary).not.toContain("12345678901-1");
     expect(summary).toContain("- **posture**: write-capable");
     expect(summary).toContain("- **created items**: 2");
     expect(summary).toContain("- **blocked requests**: 1");
@@ -67,6 +68,25 @@ describe("generate_observability_summary.cjs", () => {
     expect(mockCore.summary.write).toHaveBeenCalledTimes(1);
   });
 
+  it("falls back to workflow_call_id when otel_trace_id is absent", async () => {
+    fs.writeFileSync(
+      "/tmp/gh-aw/aw_info.json",
+      JSON.stringify({
+        workflow_name: "triage-workflow",
+        engine_id: "copilot",
+        staged: false,
+        firewall_enabled: false,
+        context: { workflow_call_id: "12345678901-1" },
+      })
+    );
+
+    await module.main(mockCore);
+
+    expect(mockCore.summary.addRaw).toHaveBeenCalledTimes(1);
+    const summary = mockCore.summary.addRaw.mock.calls[0][0];
+    expect(summary).toContain("- **trace id**: 12345678901-1");
+  });
+
   it("skips summary generation when opt-in mode is disabled", async () => {
     process.env.GH_AW_OBSERVABILITY_JOB_SUMMARY = "off";