diff --git a/e2e/cloud/codemode-cell-telemetry.test.ts b/e2e/cloud/codemode-cell-telemetry.test.ts
new file mode 100644
index 000000000..cd935d7d5
--- /dev/null
+++ b/e2e/cloud/codemode-cell-telemetry.test.ts
@@ -0,0 +1,149 @@
+import { randomBytes } from "node:crypto";
+import { createServer } from "node:http";
+
+import { expect } from "@effect/vitest";
+import { Effect } from "effect";
+import { composePluginApi } from "@executor-js/api/server";
+import { openApiHttpPlugin } from "@executor-js/plugin-openapi/api";
+import { AuthTemplateSlug, ConnectionName, IntegrationSlug } from "@executor-js/sdk/shared";
+
+import { scenario } from "../src/scenario";
+import { Api, Target, Telemetry } from "../src/services";
+
+const api = composePluginApi([openApiHttpPlugin()] as const);
+
+const upstreamSpec = (baseUrl: string): string =>
+  JSON.stringify({
+    openapi: "3.0.3",
+    info: { title: "Cell Telemetry Upstream", version: "1.0.0" },
+    servers: [{ url: baseUrl }],
+    paths: {
+      "/ok": {
+        get: {
+          operationId: "ok",
+          summary: "Succeeds",
+          tags: ["probe"],
+          responses: { "200": { description: "" } },
+        },
+      },
+    },
+  });
+
+const serveUpstream = Effect.acquireRelease(
+  Effect.callback<{ readonly baseUrl: string; readonly close: () => void }>((resume) => {
+    const server = createServer((_request, response) => {
+      response.writeHead(200, { "content-type": "application/json" });
+      response.end('{"fine":true}');
+    });
+    server.listen(0, "127.0.0.1", () => {
+      const address = server.address();
+      const port = typeof address === "object" && address ? address.port : 0;
+      resume(
+        Effect.succeed({
+          baseUrl: `http://127.0.0.1:${port}`,
+          close: () => {
+            server.close();
+            server.closeAllConnections();
+          },
+        }),
+      );
+    });
+  }),
+  (server) => Effect.sync(server.close),
+);
+
+scenario(
+  "Code mode cell tool calls carry trace correlation metadata",
+  { timeout: 180_000 },
+  Effect.scoped(
+    Effect.gen(function* () {
+      const target = yield* Target;
+      const { client: apiClient } = yield* Api;
+      const telemetry = yield* Telemetry;
+      const identity = yield* target.newIdentity();
+      const client = yield* apiClient(api, identity);
+      const upstream = yield* serveUpstream;
+
+      const slug = IntegrationSlug.make(`celltrace${randomBytes(4).toString("hex")}`);
+      yield* client.openapi.addSpec({
+        payload: {
+          spec: { kind: "blob", value: upstreamSpec(upstream.baseUrl) },
+          slug,
+          baseUrl: upstream.baseUrl,
+          authenticationTemplate: [
+            {
+              slug: "apiKey",
+              type: "apiKey",
+              headers: { Authorization: ["Bearer ", { type: "variable", name: "token" }] },
+            },
+          ],
+        },
+      });
+      yield* client.connections.create({
+        payload: {
+          owner: "org",
+          name: ConnectionName.make("main"),
+          integration: slug,
+          template: AuthTemplateSlug.make("apiKey"),
+          value: "cell-telemetry-token",
+        },
+      });
+
+      const tools = yield* client.tools.list({ query: {} });
+      const tool = tools.find(
+        (entry) =>
+          String(entry.integration) === String(slug) && String(entry.address).endsWith(".ok"),
+      );
+      expect(tool, "the OpenAPI operation is in the tool catalog").toBeDefined();
+      const address = String(tool!.address);
+      const path = address.startsWith("tools.") ? address.slice("tools.".length) : address;
+
+      const specResponse = yield* Effect.promise(() =>
+        fetch(new URL("/api/openapi.json", target.baseUrl)),
+      );
+      const spec = (yield* Effect.promise(() => specResponse.json())) as {
+        readonly paths?: Record<string, unknown>;
+      };
+      expect(Object.keys(spec.paths ?? {}), "the cell API is documented").toContain(
+        "/api/execution-cells",
+      );
+
+      const cellResponse = yield* Effect.promise(() =>
+        fetch(new URL("/api/execution-cells", target.baseUrl), {
+          method: "POST",
+          headers: {
+            ...(identity.headers ?? {}),
+            "content-type": "application/json",
+            origin: new URL(target.baseUrl).origin,
+          },
+          body: JSON.stringify({
+            yieldAfterMs: 5_000,
+            code: `return await tools.${path}({});`,
+          }),
+        }),
+      );
+      const cellBody = yield* Effect.promise(() => cellResponse.text());
+      expect(cellResponse.status, `startCell response body: ${cellBody.slice(0, 500)}`).toBe(200);
+      const cell = JSON.parse(cellBody) as {
+        readonly status?: unknown;
+        readonly cellId?: unknown;
+      };
+      expect(cell.status, "a one-shot tool call cell completes").toBe("completed");
+      expect(cell.cellId, "the completed cell response includes a cell id").toEqual(
+        expect.any(String),
+      );
+
+      const span = yield* telemetry.expectSpan({
+        operation: "executor.code.cell.tool",
+        attributes: {
+          "executor.tool.source": "code_cell",
+          "executor.tool.path": path,
+        },
+      });
+      expect(
+        span.span.tags["executor.code.cell_id"],
+        "the cell tool span carries a cell id",
+      ).toBeTruthy();
+    }),
+  ),
+);
diff --git a/packages/core/execution/src/engine.ts b/packages/core/execution/src/engine.ts
index 1f3db5a31..973b59a2e 100644
--- a/packages/core/execution/src/engine.ts
+++ b/packages/core/execution/src/engine.ts
@@ -654,7 +654,16 @@ export const createExecutionEngine = <E extends Cause.YieldableError = CodeExecu
       toolDiscoveryProvider,
     );
     const invoker: SandboxToolInvoker = {
-      invoke: (input) => baseInvoker.invoke(input),
+      invoke: (input) =>
+        baseInvoker.invoke(input).pipe(
+          Effect.withSpan("executor.code.cell.tool", {
+            attributes: {
+              "executor.code.cell_id": cell.id,
+              "executor.tool.source": "code_cell",
+              "executor.tool.path": input.path,
+            },
+          }),
+        ),
     };
 
     const fiber = yield* Effect.forkDetach(