feat(supervisor): forward traceparent + request_id to compute

.server-changes/README.md

@@ -38,6 +38,14 @@ Speed up batch queue processing by removing stalls and fixing retry race
 
 The body text (below the frontmatter) is a one-line description of the change. Keep it concise — it will appear in release notes.
 
+### Writing guidance
+
+These entries are public-facing - they ship verbatim in user-visible release notes. A few rules to keep them clean:
+
+- **One sentence is usually enough.** The body is the bullet in the changelog. If you need a paragraph, you're probably describing the implementation rather than the change.
+- **Describe behavior, not implementation.** Skip internal scopes, middleware names, library specifics, framework internals. Users care about what's different for them, not how it's wired.
+- **Never name internal tools or infra.** Observability stacks, internal services, infra components, monitoring backends, CI surfaces, AWS specifics - none of these belong in user-facing notes.
+
 ## Lifecycle
 
 1. Engineer adds a `.server-changes/` file in their PR

.server-changes/supervisor-compute-traceparent-forwarding.md

@@ -0,0 +1,6 @@
+---
+area: supervisor
+type: improvement
+---
+
+Forward `traceparent` headers on outbound calls to the compute provider so distributed traces stay continuous across services.

apps/supervisor/src/workloadManager/compute.ts

@@ -10,6 +10,7 @@ import { ComputeClient, stripImageDigest } from "@internal/compute";
 import { extractTraceparent, getRunnerId } from "../util.js";
 import type { OtlpTraceService } from "../services/otlpTraceService.js";
 import { tryCatch } from "@trigger.dev/core";
+import { fromContext } from "../wideEvents/index.js";
 
 type ComputeWorkloadManagerOptions = WorkloadManagerOptions & {
   gateway: {
@@ -46,6 +47,20 @@ export class ComputeWorkloadManager implements WorkloadManager {
       gatewayUrl: opts.gateway.url,
       authToken: opts.gateway.authToken,
       timeoutMs: opts.gateway.timeoutMs,
+      // Forward the current wide-event scope's traceparent + request_id so the
+      // downstream service continues the same trace and joins its own wide
+      // events to ours. When called outside a wide-event scope (or when wide
+      // events are disabled), `fromContext` returns undefined and propagation
+      // is skipped.
+      getPropagationHeaders: () => {
+        const state = fromContext();
+        if (!state) return {};
+        const headers: Record<string, string> = { "x-request-id": state.requestId };
+        if (state.traceparent) {
+          headers.traceparent = state.traceparent;
+        }
+        return headers;
+      },
     });
   }
 

internal-packages/compute/src/client.ts

@@ -11,6 +11,13 @@ export type ComputeClientOptions = {
   gatewayUrl: string;
   authToken?: string;
   timeoutMs: number;
+  /**
+   * Called once per outbound request to collect cross-service correlation
+   * headers (e.g. `traceparent`, `x-request-id`) from the caller's current
+   * scope. The returned record is merged onto the outbound headers. Return
+   * `{}` (or omit the option) to skip propagation.
+   */
+  getPropagationHeaders?: () => Record<string, string>;
 };
 
 export class ComputeClient {
@@ -40,6 +47,14 @@ class HttpTransport {
     if (this.opts.authToken) {
       h["Authorization"] = `Bearer ${this.opts.authToken}`;
     }
+    const propagation = this.opts.getPropagationHeaders?.();
+    if (propagation) {
+      for (const [key, value] of Object.entries(propagation)) {
+        if (value) {
+          h[key] = value;
+        }
+      }
+    }
     return h;
   }