Shepherding Pull Requests Skill

This skill allows you to automate shepherding actions on approved PRs using the shepherd.dart script. For details on how the tool works, see the README.md.

Workflow and Interaction Guidelines

When the user asks for the status of their open or approved PRs:

1. Do NOT automatically execute shepherding actions (e.g., do not run shepherd.dart run --all or shepherd.dart run --pr <number>) on the initial inquiry.
2. First, retrieve the PR states using the list command:
   bashCopy

   dart .agents/skills/shepherd-prs/scripts/shepherd.dart list
   

3. Present a clear summary of the PRs, including their current status and recommended actions.
4. Explicitly ask the user for confirmation before executing any shepherding/running actions.
5. Only proceed with executing actions (e.g., run --all or run --pr) after receiving explicit approval from the user.

Handling Execution Outputs & Edge Cases

When running the run command, inspect the returned JSON logs and handle specific results as follows:

1. Stale Branch Updates

• The tool automatically merges the default branch into the PR if it is behind by 50+ commits, or if it has a ci.yaml validation failure and is behind by at least 1 commit.
• Stale Token Scope Error: If the branch contains GitHub Actions workflow files, the update may fail with an HTTP 403 error due to a lack of workflow scope.
  • Action: If a log contains ERROR: ... lacks the "workflow" scope, do not try to rerun. Output a highly prominent note to the user asking them to refresh their CLI scope: gh auth refresh -h github.com -s workflow

2. Failed Checks & Manual Re-runs

• Due to GitHub App permission policies, third-party check runs (such as LUCI checks created by flutter-dashboard) cannot be re-run via the API.
• When a PR has failed checks, the tool will log a warning instructing you to ask the user to manually trigger the re-run via the LUCI build page or the Flutter Build Dashboard.
• Action:
  1. Print the warning and ask the user to click the "Details" link on the failed check in GitHub to go to the LUCI build page and click the "Retry Build" button.
  2. If the check run continues to fail after manual re-runs, inspect the failure logs using gh pr view <number> --repo flutter/flutter or through the checks details, and write a summary of the failure for the user.

3. Target Branch Correction

• Dismissed Reviews Warning: Changing the target branch of a PR often causes GitHub to automatically dismiss existing approvals.
  • Action: If the target branch was changed, the PR will disappear from the approved list. Output a clear note to the user informing them that the base was corrected, and they need to go to the PR page on GitHub to re-approve the PR so the automation can resume shepherding it.

4. Merge Conflicts

• The tool will log: WARNING: PR has merge conflicts. Manual intervention required.
  • Action: Inform the user about the conflict so they can ask the contributor to resolve it.

Examples

• User: "What is the status of my approved and open PRs?"

• Agent:

  1. Identifies the read-only inquiry and runs dart .agents/skills/shepherd-prs/scripts/shepherd.dart list.
  2. Parses the JSON output to present a summary of all your own open PRs and approved third-party PRs, their CI checks, and recommended actions.
  3. Asks the user for confirmation before executing any shepherding actions.

• User: "Yes, please update the branch for PR #186254."

• Agent:

  1. Identifies the user's explicit confirmation and runs dart .agents/skills/shepherd-prs/scripts/shepherd.dart run --pr 186254.
  2. Logs the result of the branch update to the user.

• User: "Run shepherding on all my eligible PRs."

• Agent:

  1. Asks the user for confirmation: "I will run shepherding on all eligible approved PRs. Would you like me to proceed?"
  2. Upon receiving confirmation, runs dart .agents/skills/shepherd-prs/scripts/shepherd.dart run --all and reports the action logs.