diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 193267c..5ac03e3 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -60,3 +60,40 @@ jobs:
 
       - name: Build
         run: pnpm build
+
+  deploy-trigger:
+    name: Deploy Trigger.dev tasks
+    # Only a merge into main ships tasks. Pull requests stop at the `ci` job so a
+    # branch never overwrites the prod deployment.
+    if: github.event_name == 'push' && github.ref == 'refs/heads/main'
+    needs: ci
+    runs-on: ubuntu-latest
+
+    env:
+      # `trigger deploy` authenticates with a Personal Access Token (tr_pat_...),
+      # NOT the TRIGGER_SECRET_KEY the app uses at runtime. Generate one at
+      # https://cloud.trigger.dev/account/tokens and store it as a repo secret.
+      TRIGGER_ACCESS_TOKEN: ${{ secrets.TRIGGER_ACCESS_TOKEN }}
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Setup pnpm
+        uses: pnpm/action-setup@v4
+
+      - name: Setup Node
+        uses: actions/setup-node@v4
+        with:
+          node-version: 22
+          cache: pnpm
+
+      - name: Install dependencies
+        run: pnpm install --frozen-lockfile
+
+      # No `prisma generate` here: nothing under `src/trigger` imports the Prisma
+      # client, so the deploy bundle never resolves `@/app/generated/prisma`.
+      # Secrets the tasks need at runtime (GOOGLE_GENERATIVE_AI_API_KEY,
+      # LIVEBLOCKS_SECRET_KEY) are set in the Trigger.dev dashboard, not here.
+      - name: Deploy tasks
+        run: pnpm exec trigger deploy
diff --git a/app/api/ai/design/route.ts b/app/api/ai/design/route.ts
index 5c8ff66..0558aba 100644
--- a/app/api/ai/design/route.ts
+++ b/app/api/ai/design/route.ts
@@ -68,10 +68,19 @@ export async function POST(request: Request) {
     return Response.json({ error: "roomId must match projectId" }, { status: 400 });
   }
 
-  const handle = await tasks.trigger<typeof designAgentTask>("design-agent", {
-    prompt: parsedBody.prompt,
-    roomId: parsedBody.roomId,
-  });
+  let handle: Awaited<ReturnType<typeof tasks.trigger<typeof designAgentTask>>>;
+  try {
+    handle = await tasks.trigger<typeof designAgentTask>("design-agent", {
+      prompt: parsedBody.prompt,
+      roomId: parsedBody.roomId,
+    });
+  } catch (error) {
+    // wrong-environment TRIGGER_SECRET_KEY, a branch env that does not exist, or
+    // no deployed version of the task. Surface it as 502 so the client does not
+    // mistake it for an expired session, and log the cause for the server side.
+    console.error("[api/ai/design] failed to trigger design-agent", error);
+    return Response.json({ error: "Design service unavailable" }, { status: 502 });
+  }
 
   await prisma.taskRun.create({
     data: {
diff --git a/context/progress-tracker.md b/context/progress-tracker.md
index db4ef30..46a3b20 100644
--- a/context/progress-tracker.md
+++ b/context/progress-tracker.md
@@ -672,3 +672,37 @@ Update this file whenever the current phase, active feature, or implementation s
       - Prisma create/update/delete verified against the restored schema: slug ids, client-side `cuid()` generation and
         `@updatedAt` all behave as before; test rows deleted
       - `pnpm lint`, `pnpm typecheck`, and `pnpm build` passed
+- Fixed the production AI design generation break on 2026-09-11:
+    - Symptom: prompting the AI in production returned nothing. Server log showed
+      `TriggerApiError: No matching branch env` (401) from `tasks.trigger`. Local runs were unaffected.
+    - Root cause: `@trigger.dev/core` resolves a preview branch from
+      `previewBranch ?? TRIGGER_PREVIEW_BRANCH ?? VERCEL_GIT_COMMIT_REF` and attaches it as the
+      `x-trigger-branch` header on every request. Vercel always sets `VERCEL_GIT_COMMIT_REF` (`main` on
+      production deploys), so the deployed app sent a branch header that resolved against a preview
+      secret key with no matching branch environment. Locally neither variable is set, so no header is
+      sent and the `tr_dev_` key resolves against the dev environment.
+    - Fix, part 1 (outside the repo): the production `TRIGGER_SECRET_KEY` on Vercel was replaced with a
+      `tr_prod_` key.
+    - Fix, part 2 — `.github/workflows/ci.yml`:
+      - Added a `deploy-trigger` job that runs `pnpm exec trigger deploy` after `ci` passes, gated to
+        pushes on `main` so pull requests never overwrite the prod deployment. Previously nothing in CI
+        deployed tasks at all, so the prod environment had no deployed version of `design-agent`.
+      - The job authenticates with `TRIGGER_ACCESS_TOKEN` (a `tr_pat_` Personal Access Token, which is a
+        different credential from the runtime `TRIGGER_SECRET_KEY`) and must be added as a repo secret.
+      - No `prisma generate` step: nothing under `src/trigger` imports the Prisma client.
+    - Fix, part 3 — `app/api/ai/design/route.ts`:
+      - Wrapped `tasks.trigger` in try/catch. The call was previously unguarded, so any Trigger.dev
+        failure escaped as an unhandled 500 and the sidebar showed only a generic message. Failures now
+        log server-side and return 502.
+    - Fix, part 4 — `hooks/use-design-agent.ts`:
+      - Added a 502 case to `describeRequestFailure` so an unreachable design service reads as such
+        rather than falling through to the generic error. 502 was chosen over 401 deliberately: the
+        hook maps 401 to "your session expired", which would misreport an infrastructure failure.
+    - Validation checks:
+      - `pnpm lint`, `pnpm typecheck`, and `pnpm build` passed
+    - Open items:
+      - `app/api/trigger/hello/route.ts` has the same unguarded `tasks.trigger` call. Left as is — it is
+        a sample route outside this fix's scope.
+      - `.claude/skills/trigger-setup/references/environment-setup.md` documents `TRIGGER_SECRET_KEY` for
+        `trigger deploy` in CI, which is wrong (the CLI requires `TRIGGER_ACCESS_TOKEN`). It is vendored
+        third-party skill content, so it was not edited.
diff --git a/hooks/use-design-agent.ts b/hooks/use-design-agent.ts
index 48d49dc..0c150ec 100644
--- a/hooks/use-design-agent.ts
+++ b/hooks/use-design-agent.ts
@@ -53,6 +53,8 @@ function describeRequestFailure(status: number): string {
       return "Your session expired. Sign in again to keep designing.";
     case 403:
       return "You do not have access to this project, so the design was not generated.";
+    case 502:
+      return "The design service is unreachable right now, so nothing was generated. Try again shortly.";
     default:
       return GENERIC_ERROR;
   }