Anchor Vet

anchor-vet

Force the skipped move in code review: prove the reviewed diff's scope, blast radius, claims, findings, and verdict are anchored to git evidence.

Trigger Check

Use this skill only when there is a concrete code change to judge: a PR, branch, commit range, or staged review target.

Boundary test: can you name a base...head pair of git states whose difference is the artifact under judgment? If yes, use anchor-vet. If no, get the branch or ref first; do not review pasted diffs or prose descriptions.

Do not use anchor-vet for design feedback without a diff, whole-codebase audits, feature implementation, bug fixing, formatting-only tasks, or document review. If the user asks you to fix findings too, render the review verdict first; fixes are a separate task, and behavioral fixes route to anchor-repro.

Forced Procedure

1. Anchor the scope. Check out the reviewed head locally. Capture external claims before init: for PRs, save the title/body from gh pr view --json title,body --jq '.title + "\n\n" + (.body // "")' to a claims file. Run: python3 skills/anchor-vet/scripts/vet_gate.py init --project <root> --review <slug> --base <ref> --head <ref> --claims-file <path> or, only when there are genuinely no external claims, --no-claims.
2. Read every hunk. Inspect the full diff and every hunk in scope.json. If the diff is too large to read honestly, stop and propose a split.
3. Walk the blast radius. For each candidate symbol, read the references found by the gate. Record examined refs with effect and a one-line note. Examined means you opened/read the reference and judged how the change affects it.
4. Account weak or symbolless hunks. For weak/symbolless hunks, use a verified enclosingUnit when a named unit exists, or file-level with a reason only for genuinely unit-less code/config/prose.
5. Cross-examine claims. Disposition every anchored claim id from scope.json: verified, contradicted, not-verifiable-from-diff, or non-claim. Verified/contradicted claims need citations.
6. Hunt findings with severity honesty. Use only blocking, concern, and nit. Cite findings. A blocking finding needs R2 cited evidence or an R3 repro probe. When a behavioral assertion is cheap to demonstrate, record a failing anchor-repro ledger entry against the reviewed head and cite it with entrySha256.
7. Write and check review.json. Run: python3 skills/anchor-vet/scripts/vet_gate.py check --project <root> --review <slug>. Fix check failures by doing the missing review work, not by padding JSON.
8. Render the verdict through the gate. Run: python3 skills/anchor-vet/scripts/vet_gate.py close --project <root> --review <slug> --verdict approve|request-changes|blocked. Report the verdict, cite verdict.json, and name each finding's evidence rung.

Script Contract

Artifacts are written under the target project:

.techne/review/<slug>/
  scope.json    # computed by init
  review.json   # authored by the reviewer
  report.json   # computed by check
  verdict.json  # computed by close

Generated .techne/ output belongs to target projects. Do not commit it to this repository.

Review skeleton:

{
  "schema": "techne.vet/1",
  "symbols": [
    {
      "id": "s-...",
      "symbol": "changedName",
      "disposition": "reviewed",
      "refs": [
        {
          "file": "src/caller.py",
          "line": 42,
          "effect": "unaffected",
          "note": "caller passes the same contract"
        }
      ]
    }
  ],
  "hunks": [],
  "claims": [
    {
      "ids": ["c-..."],
      "disposition": "verified",
      "citations": [{"file": "src/change.py", "line": 10}]
    }
  ],
  "findings": [],
  "testsAcknowledgment": "No tests changed; the diff is docs-only or existing coverage is enough because ..."
}

Use reference.md for the full JSON schema, rubrics, exclusions, weak spots, and probe guidance.

Stop Conditions

• Stop if no git-anchored base...head diff is available.
• Stop if init refuses because of dirty worktree, missing merge base, or head mismatch; fix the setup or record blocked.
• Stop if the review is too large to read in full; propose a split instead of sampling silently.
• Stop before approve if refs, hunks, claims, or test acknowledgment remain unaccounted.
• If head moves mid-review, do not fight the tool. Close the old slug as blocked --reason ... or leave it, then start a new slug for the new head.