diff --git a/src/daemon/webhook.test.ts b/src/daemon/webhook.test.ts
index e57365a..f9a5cf9 100644
--- a/src/daemon/webhook.test.ts
+++ b/src/daemon/webhook.test.ts
@@ -73,13 +73,27 @@ describe("buildWebhookPayload", () => {
     expect(payload.adapter).toBe("claude-code");
     expect(payload.cwd).toBe("/home/user/project");
     expect(payload.duration_seconds).toBe(300);
-    expect(payload.exit_status).toBe("stopped");
+    expect(payload.exit_status).toBe(0);
     expect(payload.summary).toBe("Fix the bug");
     expect(payload.meta).toEqual({
       openclaw_callback_session_key: "key-1",
     });
     expect(payload.timestamp).toBeTruthy();
   });
+
+  it("prefers explicit exitCode when present", () => {
+    const payload = buildWebhookPayload({
+      id: "sess-456",
+      adapter: "claude-code",
+      status: "failed",
+      startedAt: "2026-03-07T10:00:00.000Z",
+      stoppedAt: "2026-03-07T10:00:05.000Z",
+      exitCode: 137,
+      meta: {},
+    });
+
+    expect(payload.exit_status).toBe(137);
+  });
 });
 
 describe("computeSignature", () => {
@@ -126,7 +140,7 @@ describe("emitWebhook", () => {
     expect(opts.headers["X-Agentctl-Signature"]).toBeUndefined();
   });
 
-  it("includes HMAC signature when secret is provided", async () => {
+  it("includes HMAC signatures when secret is provided", async () => {
     const payload = buildWebhookPayload({
       id: "s1",
       adapter: "claude-code",
@@ -143,6 +157,12 @@ describe("emitWebhook", () => {
     const [, opts] = (fetch as ReturnType<typeof vi.fn>).mock.calls[0];
     expect(opts.headers["X-Agentctl-Signature"]).toBeTruthy();
     expect(opts.headers["X-Agentctl-Signature"]).toHaveLength(64);
+    expect(opts.headers["X-Signature"]).toBe(
+      `sha256=${opts.headers["X-Agentctl-Signature"]}`,
+    );
+    expect(opts.headers["X-Hub-Signature-256"]).toBe(
+      `sha256=${opts.headers["X-Agentctl-Signature"]}`,
+    );
   });
 
   it("does not throw on fetch failure", async () => {
diff --git a/src/daemon/webhook.ts b/src/daemon/webhook.ts
index c893122..0c3369b 100644
--- a/src/daemon/webhook.ts
+++ b/src/daemon/webhook.ts
@@ -12,7 +12,7 @@ export interface WebhookPayload {
   cwd?: string;
   adapter: string;
   duration_seconds: number;
-  exit_status: string;
+  exit_status: number;
   summary?: string;
   meta: Record<string, unknown>;
   timestamp: string;
@@ -47,13 +47,17 @@ export function buildWebhookPayload(session: SessionRecord): WebhookPayload {
     Math.round((stoppedAt - startedAt) / 1000),
   );
 
+  const exitStatus =
+    session.exitCode ??
+    (session.status === "error" || session.status === "failed" ? 1 : 0);
+
   return {
     hook_type: "session.stopped",
     session_id: session.id,
     cwd: session.cwd,
     adapter: session.adapter,
     duration_seconds: durationSeconds,
-    exit_status: session.status,
+    exit_status: exitStatus,
     summary: session.prompt?.slice(0, 200),
     meta: session.meta ?? {},
     timestamp: new Date().toISOString(),
@@ -81,10 +85,10 @@ export async function emitWebhook(
     };
 
     if (webhookConfig.secret) {
-      headers["X-Agentctl-Signature"] = computeSignature(
-        body,
-        webhookConfig.secret,
-      );
+      const signature = computeSignature(body, webhookConfig.secret);
+      headers["X-Agentctl-Signature"] = signature;
+      headers["X-Signature"] = `sha256=${signature}`;
+      headers["X-Hub-Signature-256"] = `sha256=${signature}`;
     }
 
     // Use global fetch (available in Node 18+)