---
name: Checkout Credential Review
slug: checkout-credential-review
category: Quality
description: Checkout Credential Review helps review code that performs git or gh operations against repository checkouts, ensuring the right credentials are available at the right time and that sparseness, shallowness, and credential-free factors are considered.
github: "https://github.com/github/gh-aw/tree/main/.github/skills/checkout-credential-review"
language: Go
stars: 4934
forks: 495
install: "npx degit https://github.com/github/gh-aw/tree/main/.github/skills/checkout-credential-review ~/.claude/skills/checkout-credential-review"
installs_to: ~/.claude/skills/checkout-credential-review
source_path: .github/skills/checkout-credential-review/SKILL.md
collection_size: 25
category_size: 1354
collection_url: "https://dirskills.com/collections/github/gh-aw"
added: 2026-08-16T07:00:52.338Z
last_synced: 2026-08-16T07:00:52.338Z
canonical_url: "https://dirskills.com/skills/checkout-credential-review"
---

# Checkout Credential Review

Checkout Credential Review helps review code that performs git or gh operations against repository checkouts, ensuring the right credentials are available at the right time and that sparseness, shallowness, and credential-free factors are considered.

**Install:**

```bash
npx degit https://github.com/github/gh-aw/tree/main/.github/skills/checkout-credential-review ~/.claude/skills/checkout-credential-review
```

## README

# Checkout Credential Review

Use this skill when reviewing or writing code in `pkg/workflow/`, `actions/setup/js/`, or compiled `.lock.yml` workflows that runs `git`, `gh`, or any other remote-touching operation against a repository checkout.

## Background

Each entry in a workflow's `checkout:` block may declare its own credentials (`github-token:`, `github-app:`), and the compiler wires those into the corresponding `actions/checkout` step ([pkg/workflow/checkout_step_generator.go](../../../pkg/workflow/checkout_step_generator.go)). Generated checkouts always set `persist-credentials: false`, so the on-disk repo retains **no** credentials after the step finishes — only `actions/checkout`'s own internal token is used during the clone, and it is scrubbed in its post-step.

A separate step that wants to authenticate later must either (a) re-inject a token at command level (e.g. `git -c http.extraheader=...`) or (b) be passed the per-checkout token via env. The compiler does *not* automatically thread per-checkout `github-token`s into downstream steps.

Two important contexts deliberately run with **no git credentials**:

- The **safe-outputs MCP server** and its handlers (`generate_git_bundle.cjs`, `generate_git_patch.cjs`, `create_pull_request.cjs`). Errors in these paths explicitly say "the safe-outputs MCP server has no credentials for private repositories" — fetch/push will fail for private repos.
- The **agent runtime** after `actions/checkout`. The agent prompt in [actions/setup/md/safe_outputs_push_to_pr_branch.md](../../../actions/setup/md/safe_outputs_push_to_pr_branch.md) explicitly tells the model not to attempt `git fetch`, `git pull`, `git push`, or any other authenticated git operation, and to report unavailable branches rather than try to fetch them.

## Review checklist

When you see a new `git`, `gh`, `execFileSync('git'…)`, or compiled `run:` block:

1. **Does it touch a remote?** Local-only commands (`symbolic-ref`, `rev-parse`, `log`, `show`, `merge-base`, `diff`, `status`) need no credentials. Anything in `fetch | pull | push | clone | ls-remote | remote (set-url|add|update)` does, plus on-demand blob fetches in partial clones.
2. **Which checkout is it operating on?** If it's a cross-repo entry from `checkout:`, the relevant credential is *that entry's* `github-token`, not the workflow's default `GITHUB_TOKEN`. Confirm the per-entry token is actually threaded into the step's env (or refuse to do remote operations and degrade gracefully).
3. **Which job/context emits it?** Agent job and safe-outputs MCP server both run without git credentials by design. Any remote git operation there must be wrapped in `try/catch`, fail soft, and surface a clear "no credentials" error rather than a raw git stderr.
4. **Sparse / shallow / monorepo concerns.** Avoid emitting steps that deepen (`git fetch --unshallow`, `--deepen=N`) or widen (`git fetch origin '+refs/heads/*'`) a sparse or shallow checkout of a large monorepo — these need credentials *and* can pull hundreds of MB. Prefer expanding `fetch:` / `fetch-depth:` / `sparse-checkout:` at compile time so it happens during `actions/checkout` with its internal token, never later.
5. **`gh` is REST, not git.** `gh api …` uses whatever `GH_TOKEN` is in the step's env — it does **not** automatically inherit per-checkout PATs. For cross-org private repos, either thread the right token in or accept the call will 404 and handle it.

## Related

- [docs/src/content/docs/reference/checkout.md](../../../docs/src/content/docs/reference/checkout.md) — "Git Credentials After Checkout"
- [docs/sparseness.md](../../../docs/sparseness.md) — sparse/blobless credential lifecycle
- [pkg/workflow/checkout_step_generator.go](../../../pkg/workflow/checkout_step_generator.go) — token wiring per checkout
- [actions/setup/md/safe_outputs_push_to_pr_branch.md](../../../actions/setup/md/safe_outputs_push_to_pr_branch.md) — agent-facing guidance