Require explicit noop signal in Code Scanning Fixer to prevent false failures on API errors

[Copilot]

The Code Scanning Fixer workflow failed with missing finish_reason for choice 0 despite successfully finding no alerts to fix. This transient Copilot API error occurred after the agent completed its work, causing spurious failure tracking issues.

Changes

• Added explicit success signaling: Require agent to call noop tool when no alerts are found
• Updated error handling: Changed from implicit "exit gracefully" to explicit noop(message="...") calls
• Added documentation: Explain that noop signals persist even if CLI fails afterward

Why this works

The safe output system captures noop calls independently of CLI completion. When the API fails mid-response, the previously recorded noop signal indicates successful completion, preventing false failure reports.

Before:

- If no unfixed high severity alerts remain, exit gracefully with message: "..."

After:

- If no unfixed high severity alerts remain:
  - **MUST** call `noop(message="No unfixed high severity alerts found...")`
  - This signals successful completion and prevents transient API errors from being reported as failures
  - Exit gracefully

The workflow now distinguishes between genuine failures (agent couldn't complete work) and transient API errors (agent completed work, CLI failed afterward).

Original prompt

---

This section details on the original issue you should resolve

<issue_title>[agentics] Code Scanning Fixer failed</issue_title>
<issue_description>### Workflow Failure

Workflow: Code Scanning Fixer
Branch: main
Run URL: https://github.com/githubnext/gh-aw/actions/runs/21126053891

Action Required

Debug this workflow failure using the agentic-workflows agent:

/agent agentic-workflows

When prompted, instruct the agent to debug this workflow failure.

Generated from Code Scanning Fixer

• expires on Jan 26, 2026, 5:11 AM UTC

Comments on the Issue (you are @copilot in this section)

• Fixes [agentics] Code Scanning Fixer failed #10645

---

✨ Let Copilot coding agent set things up for you — coding agent works faster and does higher quality work when set up for your repo.

[pelikhan]

@copilot format, lint

[Copilot]

@pelikhan Unfortunately I hit an unexpected error while processing your comment. I've automatically reported this to GitHub.

You can ask me to try again later by mentioning me in a new comment.

If you want to contact GitHub about this error, please mention the following identifier so they can better serve you: 5d597c78-c1d0-4d6d-8b6d-793282545f33

Sorry for the inconvenience!