ci: fail jobs that dirty the worktree (#29720)

## Why

CI jobs should not silently leave tracked changes or untracked files in
the repository worktree.

## What

- Add a shared final worktree-cleanliness action to 19 checkout-bearing
PR and main CI jobs.
- Ignore the intentional SDK scratch directory and nested V8 checkout.
- Pin Bazelisk in shared CI setup so `.bazelversion` remains
authoritative, avoiding `MODULE.bazel.lock` deltas on Windows runners.
- Leave `rust-ci-full` and release-only workflows unchanged.
- Update `AGENTS.md` to discourage review bots from asking for
`MODULE.bazel.lock` changes.

.github/actions/check-clean-worktree/action.yml

@@ -0,0 +1,19 @@
+name: check-clean-worktree
+description: Fail when a CI job leaves tracked changes or untracked files in the repository worktree.
+
+runs:
+  using: composite
+  steps:
+    - name: Check for a clean worktree
+      shell: bash
+      run: |
+        set -euo pipefail
+
+        status="$(git -C "${GITHUB_WORKSPACE}" status --porcelain=v1 --untracked-files=normal --ignore-submodules=none)"
+        if [[ -z "${status}" ]]; then
+          exit 0
+        fi
+
+        echo "::error::CI job left tracked changes or untracked files in the repository worktree"
+        printf '%s\n' "${status}"
+        exit 1

.github/actions/setup-bazel-ci/action.yml

@@ -34,6 +34,10 @@ runs:
 
     - name: Set up Bazel
       uses: bazel-contrib/setup-bazel@c5acdfb288317d0b5c0bbd7a396a3dc868bb0f86 # 0.19.0
+      # Without an explicit Bazelisk version, setup-bazel leaves PATH unchanged
+      # and Windows can use the runner's standalone Bazel, ignoring .bazelversion.
+      with:
+        bazelisk-version: 1.28.1
 
     - name: Configure Bazel repository cache
       id: configure_bazel_repository_cache

.github/workflows/bazel.yml

@@ -134,6 +134,10 @@ jobs:
           path: ${{ steps.prepare_bazel.outputs.repository-cache-path }}
           key: ${{ steps.prepare_bazel.outputs.repository-cache-key }}
 
+      - name: Check for a clean worktree
+        if: always() && !cancelled()
+        uses: ./.github/actions/check-clean-worktree
+
   test-windows-shard:
     # Split the Windows Bazel test leg across separate Windows hosts. Jobs with
     # BuildBuddy credentials use Linux RBE for build actions; test execution
@@ -239,6 +243,10 @@ jobs:
           path: ${{ runner.temp }}/bazel-execution-logs
           if-no-files-found: ignore
 
+      - name: Check for a clean worktree
+        if: always() && !cancelled()
+        uses: ./.github/actions/check-clean-worktree
+
   test-windows:
     # Preserve the existing required-check surface while the real work happens
     # in the sharded Windows jobs above.
@@ -333,6 +341,10 @@ jobs:
           path: ${{ steps.prepare_bazel.outputs.repository-cache-path }}
           key: ${{ steps.prepare_bazel.outputs.repository-cache-key }}
 
+      - name: Check for a clean worktree
+        if: always() && !cancelled()
+        uses: ./.github/actions/check-clean-worktree
+
   clippy:
     timeout-minutes: 30
     strategy:
@@ -433,6 +445,10 @@ jobs:
           path: ${{ steps.prepare_bazel.outputs.repository-cache-path }}
           key: ${{ steps.prepare_bazel.outputs.repository-cache-key }}
 
+      - name: Check for a clean worktree
+        if: always() && !cancelled()
+        uses: ./.github/actions/check-clean-worktree
+
   verify-release-build:
     timeout-minutes: 30
     strategy:
@@ -545,3 +561,7 @@ jobs:
         with:
           path: ${{ steps.prepare_bazel.outputs.repository-cache-path }}
           key: ${{ steps.prepare_bazel.outputs.repository-cache-key }}
+
+      - name: Check for a clean worktree
+        if: always() && !cancelled()
+        uses: ./.github/actions/check-clean-worktree

.github/workflows/blob-size-policy.yml

@@ -32,3 +32,7 @@ jobs:
             --head "$HEAD_SHA" \
             --max-bytes 512000 \
             --allowlist .github/blob-size-allowlist.txt
+
+      - name: Check for a clean worktree
+        if: always() && !cancelled()
+        uses: ./.github/actions/check-clean-worktree

.github/workflows/cargo-deny.yml

@@ -32,3 +32,7 @@ jobs:
         with:
           rust-version: 1.95.0
           manifest-path: ./codex-rs/Cargo.toml
+
+      - name: Check for a clean worktree
+        if: always() && !cancelled()
+        uses: ./.github/actions/check-clean-worktree

.github/workflows/ci.yml

@@ -88,3 +88,7 @@ jobs:
 
       - name: Prettier (run `pnpm run format:fix` to fix)
         run: pnpm run format
+
+      - name: Check for a clean worktree
+        if: always() && !cancelled()
+        uses: ./.github/actions/check-clean-worktree

.github/workflows/codespell.yml

@@ -28,3 +28,7 @@ jobs:
         uses: codespell-project/actions-codespell@8f01853be192eb0f849a5c7d721450e7a467c579 # v2.2
         with:
           ignore_words_file: .codespellignore
+
+      - name: Check for a clean worktree
+        if: always() && !cancelled()
+        uses: ./.github/actions/check-clean-worktree

.github/workflows/rust-ci.yml

@@ -58,6 +58,10 @@ jobs:
           echo "codex=$codex" >> "$GITHUB_OUTPUT"
           echo "workflows=$workflows" >> "$GITHUB_OUTPUT"
 
+      - name: Check for a clean worktree
+        if: always() && !cancelled()
+        uses: ./.github/actions/check-clean-worktree
+
   # --- Fast Cargo-native PR checks -------------------------------------------
   general:
     name: Format / etc
@@ -83,6 +87,10 @@ jobs:
       - name: Rust benchmark smoke test
         run: just bench-smoke
 
+      - name: Check for a clean worktree
+        if: always() && !cancelled()
+        uses: ./.github/actions/check-clean-worktree
+
   cargo_shear:
     name: cargo shear
     runs-on: ubuntu-24.04
@@ -103,6 +111,10 @@ jobs:
       - name: cargo shear
         run: cargo shear --deny-warnings
 
+      - name: Check for a clean worktree
+        if: always() && !cancelled()
+        uses: ./.github/actions/check-clean-worktree
+
   argument_comment_lint_package:
     name: Argument comment lint package
     runs-on: ubuntu-24.04
@@ -154,6 +166,10 @@ jobs:
         env:
           RUST_MIN_STACK: "8388608" # 8 MiB
 
+      - name: Check for a clean worktree
+        if: always() && !cancelled()
+        uses: ./.github/actions/check-clean-worktree
+
   argument_comment_lint_prebuilt:
     name: Argument comment lint - ${{ matrix.name }}
     runs-on: ${{ matrix.runs_on || matrix.runner }}
@@ -205,6 +221,10 @@ jobs:
           target: ${{ runner.os }}
           buildbuddy-api-key: ${{ secrets.BUILDBUDDY_API_KEY }}
 
+      - name: Check for a clean worktree
+        if: always() && !cancelled() && steps.argument_comment_lint_gate.outputs.run == 'true'
+        uses: ./.github/actions/check-clean-worktree
+
   # --- Gatherer job that you mark as the ONLY required status -----------------
   results:
     name: CI results (required)

.github/workflows/sdk.yml

@@ -41,6 +41,10 @@ jobs:
               /tmp/uv/bin/uv run --frozen --no-sync pytest
             '
 
+      - name: Check for a clean worktree
+        if: always() && !cancelled()
+        uses: ./.github/actions/check-clean-worktree
+
   sdks:
     runs-on:
       group: ${{ github.event.repository.name }}-runners
@@ -161,3 +165,7 @@ jobs:
           path: |
             ~/.cache/bazel-repo-cache
           key: bazel-cache-x86_64-unknown-linux-gnu-${{ hashFiles('MODULE.bazel', 'codex-rs/Cargo.lock', 'codex-rs/Cargo.toml') }}
+
+      - name: Check for a clean worktree
+        if: always() && !cancelled()
+        uses: ./.github/actions/check-clean-worktree

.github/workflows/v8-canary.yml

@@ -97,6 +97,10 @@ jobs:
           echo "${output}"
           echo "${output}" >> "${GITHUB_OUTPUT}"
 
+      - name: Check for a clean worktree
+        if: always() && !cancelled()
+        uses: ./.github/actions/check-clean-worktree
+
   build:
     name: Build ${{ matrix.variant }} ${{ matrix.target }}
     needs: metadata
@@ -322,6 +326,10 @@ jobs:
           name: v8-canary-${{ needs.metadata.outputs.v8_version }}-${{ matrix.variant }}-${{ matrix.target }}
           path: dist/${{ matrix.target }}/*
 
+      - name: Check for a clean worktree
+        if: always() && !cancelled()
+        uses: ./.github/actions/check-clean-worktree
+
   build-windows-source:
     name: Build ptrcomp-sandbox ${{ matrix.target }} from source
     needs: metadata
@@ -459,3 +467,7 @@ jobs:
         with:
           name: v8-canary-${{ needs.metadata.outputs.v8_version }}-ptrcomp-sandbox-${{ matrix.target }}
           path: dist/${{ matrix.target }}/*
+
+      - name: Check for a clean worktree
+        if: always() && !cancelled()
+        uses: ./.github/actions/check-clean-worktree

.gitignore

@@ -60,6 +60,8 @@ yarn-error.log*
 # ci
 .vercel/
 .netlify/
+/.tmp/sdk-ci/
+/upstream-rusty-v8/
 
 # patches
 apply_patch/

AGENTS.md

@@ -35,9 +35,8 @@ In the codex-rs folder where the rust code lives:
 - When working with MCP tool calls, prefer using `codex-rs/codex-mcp/src/mcp_connection_manager.rs` to handle mutation of tools and tool calls. Aim to minimize the footprint of changes and leverage existing abstractions rather than plumbing code through multiple levels of function calls.
 - Do not call `reset_client_session` unnecessarily; let the incremental check logic decide whether to reuse the previous request.
 - If you change Rust dependencies (`Cargo.toml` or `Cargo.lock`), run `just bazel-lock-update` from the
-  repo root to refresh `MODULE.bazel.lock`, and include that lockfile update in the same change.
-- After dependency changes, run `just bazel-lock-check` from the repo root so lockfile drift is caught
-  locally before CI.
+  repo root to refresh `MODULE.bazel.lock`, and include that lockfile update in the same change. CI
+  verifies lockfile drift.
 - Bazel does not automatically make source-tree files available to compile-time Rust file access. If
   you add `include_str!`, `include_bytes!`, `sqlx::migrate!`, or similar build-time file or
   directory reads, update the crate's `BUILD.bazel` (`compile_data`, `build_script_data`, or test