diff --git a/src/commands/deploy.test.ts b/src/commands/deploy.test.ts
index 868a126..33ba3bb 100644
--- a/src/commands/deploy.test.ts
+++ b/src/commands/deploy.test.ts
@@ -102,6 +102,33 @@ describe("runDeploy", () => {
     expect(console.log).toHaveBeenCalledWith("Deployment completed: dep-1");
   });
 
+  it("includes capacity error when --wait times out with queued job error", async () => {
+    vi.useFakeTimers();
+
+    getDeployment.mockResolvedValue({
+      id: "dep-1",
+      org_id: "org-1",
+      project_id: "proj-1",
+      build_id: "build-1",
+      status: "queued",
+      mode: "drain",
+      bullmq_job_id: "job-1",
+      error:
+        "CLUSTER_NO_CAPACITY: deploy_admission cpu_deficit=255m memory_deficit=0",
+      created_at: "2026-01-01T00:00:00Z",
+      completed_at: null,
+    });
+
+    const promise = runDeploy({
+      wait: true,
+      pollIntervalMs: 1,
+      timeoutMs: 5_000,
+    });
+    const rejection = expect(promise).rejects.toThrow(/CLUSTER_NO_CAPACITY/);
+    await vi.advanceTimersByTimeAsync(10_000);
+    await rejection;
+  });
+
   it("includes last queued status when --wait times out", async () => {
     vi.useFakeTimers();
 
diff --git a/src/commands/deploy.ts b/src/commands/deploy.ts
index 77acd30..7edc91d 100644
--- a/src/commands/deploy.ts
+++ b/src/commands/deploy.ts
@@ -29,6 +29,7 @@ async function pollDeployment(
       progressId: job.build_id,
     }),
     getRetryAfterMs: (job) => job.retry_after_ms,
+    getLastDetail: (job) => job.error,
     onPoll: (job) => logVerbose(`deployment ${jobId}: status=${job.status}`),
     baseIntervalMs: options.pollIntervalMs,
     timeoutMs: options.timeoutMs,
diff --git a/src/lib/poll-backoff.test.ts b/src/lib/poll-backoff.test.ts
index 2d7f68a..6e25113 100644
--- a/src/lib/poll-backoff.test.ts
+++ b/src/lib/poll-backoff.test.ts
@@ -198,6 +198,37 @@ describe("pollWithBackoff", () => {
     expect(pollCount).toBeLessThan(5);
   });
 
+  it("includes last detail after status when timeout elapses", async () => {
+    vi.useFakeTimers();
+
+    const promise = pollWithBackoff({
+      poll: async () => ({
+        status: "queued",
+        build_id: "build-1",
+        error:
+          "CLUSTER_NO_CAPACITY: deploy_admission cpu_deficit=255m memory_deficit=0",
+      }),
+      isTerminal: () => false,
+      getProgress: (job) => ({
+        status: job.status,
+        progressId: job.build_id,
+      }),
+      getLastDetail: (job) => job.error,
+      baseIntervalMs: 1000,
+      timeoutMs: 5_000,
+      timeoutMessage: "timed out",
+      runtime: {
+        sleep: (ms) => vi.advanceTimersByTimeAsync(ms),
+        now: () => Date.now(),
+        random: () => 0.5,
+      },
+    });
+
+    await expect(promise).rejects.toThrow(
+      /timed out \(last status=queued; CLUSTER_NO_CAPACITY: deploy_admission cpu_deficit=255m memory_deficit=0\)/,
+    );
+  });
+
   it("includes last status=none when timeout elapses before any poll", async () => {
     await expect(
       pollWithBackoff({
diff --git a/src/lib/poll-backoff.ts b/src/lib/poll-backoff.ts
index 9c115b4..b31045a 100644
--- a/src/lib/poll-backoff.ts
+++ b/src/lib/poll-backoff.ts
@@ -119,6 +119,8 @@ export async function pollWithBackoff<T>(options: {
   isTerminal: (value: T) => boolean;
   getProgress: (value: T) => PollProgressSnapshot;
   getRetryAfterMs?: (value: T) => number | null | undefined;
+  /** Optional extra detail appended after last status on timeout (e.g. deploy job error). */
+  getLastDetail?: (value: T) => string | null | undefined;
   onPoll?: (value: T) => void;
   baseIntervalMs: number;
   timeoutMs: number;
@@ -130,9 +132,11 @@ export async function pollWithBackoff<T>(options: {
   let attemptIndex = 0;
   let previousProgress: PollProgressSnapshot | null = null;
   let lastProgress: PollProgressSnapshot | null = null;
+  let lastValue: T | null = null;
 
   while (runtime.now() - started < options.timeoutMs) {
     const value = await options.poll();
+    lastValue = value;
     options.onPoll?.(value);
     if (options.isTerminal(value)) {
       return value;
@@ -156,8 +160,14 @@ export async function pollWithBackoff<T>(options: {
     await runtime.sleep(delayMs);
   }
 
+  const lastDetail =
+    lastValue != null ? options.getLastDetail?.(lastValue) : undefined;
+  const detailSuffix =
+    lastDetail != null && lastDetail.trim() !== ""
+      ? `; ${lastDetail.trim()}`
+      : "";
   const lastStatusSuffix = lastProgress
-    ? ` (last status=${lastProgress.status})`
+    ? ` (last status=${lastProgress.status}${detailSuffix})`
     : ` (last status=none)`;
   throw new Error(`${options.timeoutMessage}${lastStatusSuffix}`);
 }