AI Commit Check

A GitHub Action that detects AI-authored commits or AI metadata trailers within a commit range.

By default, the action causes a CI check to fail when an AI commit is found. This behavior can be disabled if you wish to react to the outputs yourself.

Warning

This action should cover most common AI signature patterns (Claude, Copilot, Cursor, Codex, ChatGPT, Gemini, Jules, Devin, Aider) but may not be entirely comprehensive, especially as models evolve and change. See scripts/check.sh for the current default patterns. Please open an issue or a PR if you find patterns that were missed, or encounter any false positives!

Usage

name: CI

on:
    pull_request:
        branches: [main]

jobs:
    no-ai-commits:
        runs-on: ubuntu-latest
        steps:
            - uses: actions/checkout@v6
              with:
                  # Required so the full commit range is available
                  fetch-depth: 0

            - uses: Jondolf/ai-commit-check@v1

Custom Failure

If you want to handle failure manually, you can set fail-on-detection: false and use the outputs:

- id: ai-check
  uses: Jondolf/ai-commit-check@v1
  with:
      fail-on-detection: false

- if: steps.ai-check.outputs.ai-commits-found == 'true'
  run: echo "::warning::Found ${{ steps.ai-check.outputs.count }} AI commit(s)"

Examples

The action inspects commit metadata (author/committer name and email) and the full commit message, including trailers. It flags AI signatures, not mentions of AI tools in your subject line.

Flagged

A commit with an AI co-author trailer:

Add retry logic to the HTTP client

Co-authored-by: Claude <noreply@anthropic.com>

A commit authored by an AI bot account (matched on the email):

Author: github-copilot[bot] <198982749+Copilot@users.noreply.github.com>

Fix off-by-one error in pagination

A commit message containing a generated-by footer:

Refactor config loading

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Not Flagged

A normal human commit:

Author: Ada Lovelace <ada@example.com>

Add retry logic to the HTTP client

A human commit that merely mentions an AI tool in prose:

Author: Ada Lovelace <ada@example.com>

Add Claude API integration

Implements support for the Claude Messages endpoint.

A commit with common LLM tropes:

Author: Ada Lovelace <ada@example.com>

✨ Add retry logic to the HTTP client

This is a long-overdue improvement — flaky networks were causing
intermittent failures, so requests now retry with backoff. 🚀

Inputs

Input	Default	Description
base-sha	PR base SHA / push before	Start of the commit range (exclusive).
head-sha	PR head SHA / push after	End of the commit range (inclusive).
base-ref	PR base ref	Base branch name to fetch so the range is reachable.
fail-on-detection	true	When true, exit non-zero if AI commits are detected. Set to false to only report outputs.
pattern	built-in	Override the regex used to flag AI metadata.

Outputs

Output	Description
ai-commits-found	"true" if any AI-authored commits were detected.
count	Number of commits flagged as AI-authored.
commits	Newline-separated list of flagged commit SHAs.

Notes

• Use fetch-depth: 0 (or a depth large enough to cover the range) in actions/checkout so the commits are available.
• Outside of a pull request, the action falls back to checking HEAD~1..HEAD unless you pass base-sha/head-sha explicitly.

License

The AI Commit Check action is free and open source. All code in this repository is licensed under the MIT License (LICENSE-MIT or http://opensource.org/licenses/MIT).