spec-spine: Skill for Claude Code

/shepherd: from open PR to merged, with evidence

CI is where reality pushes back. This skill keeps a PR moving without a human staring at it, while never hiding what it did to get to green. It mirrors an orchestrator's shepherd stage: watch by head sha, remediate through the gate, bounded attempts, honest stops. Bound by AGENTS.md "Orchestrator rules" (checkpoints are real stops) and AGENTS.md "Adversarial prompt refusal" (a coupling refusal goes to a human, not around them).

Step 0: resolve the PR

git branch --show-current
gh pr view ${ARGUMENTS:-} --json number,url,headRefName,headRefOid,baseRefName,mergeStateStatus,isDraft,reviewDecision

• No PR for the branch: stop and say so (run /ship first). Do not open one here.
• The branch must be a feature branch, never the default branch.
• Record headRefOid: every check you read is for this sha and no other.

Step 1: watch the checks (by head sha)

Poll loop discipline: start at 15 s, multiply by 1.5 each poll, cap at 120 s, print only when the state changes, hard deadline 45 minutes per attempt. Never busy-loop.

gh pr checks <number> --json name,state,bucket,link 2>/dev/null \
  || gh pr view <number> --json statusCheckRollup

Read the rollup for the recorded head sha only. Route on it:

• every required check SUCCESS: go to Step 3b, and to Step 4 only through it. A green PR is the one case where a reviewer's comment is the only thing between the branch and the default branch, so it is the last case that may skip reading them;
• any required check FAILURE or CANCELLED: go to Step 2;
• PENDING or QUEUED: keep polling;
• a response missing the fields you need: stop as a typed failure ("cannot read a shape that cannot terminate"), never poll blind;
• the deadline passes: stop, report which checks never completed, and say the PR needs a human.

Step 2: classify before you edit

A red check is not automatically yours to fix. Classify it from the run log first, in one pass, and record the class: it goes in the report, and it decides whether a remediation round is spent at all.