Prepend system bin dirs to PATH when allowed_non_write_users is set (#1208)

Ensures later steps resolve standard tools like git and tar from /usr/bin
regardless of what setup actions added earlier in the job. Also strengthens
the PAT guidance in security.md.

🏠 Remote-Dev: homespace

action.yml

@@ -233,6 +233,14 @@ runs:
         mkdir -p "$GITHUB_ACTION_PATH/bin"
         cp "$(command -v bun)" "$GITHUB_ACTION_PATH/bin/bun"
 
+    - name: Prepend system bin dirs to PATH
+      if: ${{ inputs.allowed_non_write_users != '' && runner.os != 'Windows' }}
+      continue-on-error: true
+      shell: /bin/bash --noprofile --norc -e -o pipefail {0}
+      run: |
+        echo "/usr/bin" >> "$GITHUB_PATH"
+        echo "/bin" >> "$GITHUB_PATH"
+
     - name: Run Claude Code Action
       id: run
       shell: bash
@@ -342,6 +350,32 @@ runs:
         OTEL_LOGS_EXPORT_INTERVAL: ${{ env.OTEL_LOGS_EXPORT_INTERVAL }}
         OTEL_RESOURCE_ATTRIBUTES: ${{ env.OTEL_RESOURCE_ATTRIBUTES }}
 
+    - name: Re-prepend system bin dirs to PATH
+      if: ${{ always() && inputs.allowed_non_write_users != '' && runner.os != 'Windows' }}
+      continue-on-error: true
+      shell: /bin/bash --noprofile --norc -e -o pipefail {0}
+      env:
+        BASH_ENV: ""
+        LD_PRELOAD: ""
+        LD_LIBRARY_PATH: ""
+        NODE_OPTIONS: ""
+        DYLD_INSERT_LIBRARIES: ""
+        DYLD_PRELOAD: ""
+        DYLD_LIBRARY_PATH: ""
+        DYLD_FRAMEWORK_PATH: ""
+      run: |
+        echo "/usr/bin" >> "$GITHUB_PATH"
+        echo "/bin" >> "$GITHUB_PATH"
+        {
+          echo "BASH_ENV="
+          echo "LD_PRELOAD="
+          echo "LD_LIBRARY_PATH="
+          echo "DYLD_INSERT_LIBRARIES="
+          echo "DYLD_PRELOAD="
+          echo "DYLD_LIBRARY_PATH="
+          echo "DYLD_FRAMEWORK_PATH="
+        } >> "$GITHUB_ENV"
+
     - name: Cleanup SSH signing key
       if: always() && inputs.ssh_signing_key != ''
       shell: bash

docs/security.md

@@ -15,7 +15,7 @@
   - Is designed for automation workflows where user permissions are already restricted by the workflow's permission scope
   - When set, Claude does a best-effort scrub of Anthropic, cloud, and GitHub Actions secrets from subprocess environments. On Linux runners with bubblewrap available, subprocesses additionally run with PID-namespace isolation. This reduces but does not eliminate prompt injection risk — keep workflow permissions minimal and validate all outputs. Set `CLAUDE_CODE_SUBPROCESS_ENV_SCRUB: 0` in your workflow or job `env:` block to opt out.
   - Optionally set `CLAUDE_CODE_SCRIPT_CAPS` in your workflow `env:` block to limit how many times Claude can call specific scripts per run. Value is JSON: `{"script-name.sh": maxCalls}`. Example: `CLAUDE_CODE_SCRIPT_CAPS: '{"edit-issue-labels.sh":2}'` allows at most 2 calls to `edit-issue-labels.sh`. Useful for write-capable helper scripts.
-  - When using `allowed_non_write_users`, always pass `github_token: ${{ secrets.GITHUB_TOKEN }}`. The auto-generated workflow token is scoped to the job's declared permissions and expires automatically, which limits blast radius. Personal access tokens are not recommended for untrusted-input workflows.
+  - When using `allowed_non_write_users`, always pass `github_token: ${{ secrets.GITHUB_TOKEN }}`. The auto-generated workflow token is scoped to the job's declared permissions and expires when the job completes. **Do not use a personal access token** — a static token does not rotate between runs, and depending on the tools allowed via `claude_args`, the model could be used to recover part or all of it. We recommend restricting allowed tools (e.g. `claude_args: '--allowedTools "Bash(gh issue view:*)"'`) to the minimum required when using `allowed_non_write_users`.
 - **Token Permissions**: The GitHub app receives only a short-lived token scoped specifically to the repository it's operating in
 - **No Cross-Repository Access**: Each action invocation is limited to the repository where it was triggered
 - **Limited Scope**: The token cannot access other repositories or perform actions beyond the configured permissions