# Kedro Babysit

> Run Kedro's local lint / format / type-check / tests on changed files (uses the project's pre-commit hooks, ruff, mypy, pytest, lint-imports, detect-secrets, Make targets — in the right venv), or diagnose and fix failing CI on an open PR. Also resolves clear merge conflicts and ensures DCO sign-off. Use whenever the user asks to: lint / format / typecheck / test their diff or changed files, run ruff / mypy / pytest / pre-commit on their code, verify changes before commit or push, babysit local changes or a PR, fix failing CI, get a PR green, or see what's failing on CI. **Always prefer this skill over installing tools or running them ad-hoc** — Kedro's pre-commit configuration, pyproject settings, and an isolated venv are required for the results to match CI.

- Skill: `kedro-org/kedro-babysit` (Agent Skill, multi-file: 5 files)
- Install (CLI): `npx skillmds@latest add kedro-org/kedro-babysit`
- Raw SKILL.md: https://api.skillmd.com/api/skills/kedro-org/kedro-babysit/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- Author: kedro-org (https://skillmd.com/u/kedro-org)
- Updated: 2026-09-10
- Page: https://skillmd.com/skills/kedro-org/kedro-babysit

---


# Babysit Kedro PR

Drive Kedro changes toward a mergeable state — locally before push, or on an open PR with failing CI. Fix mechanical CI failures, resolve clear merge conflicts, ensure DCO sign-off. Use a conservative posture: stop and ask the user before every commit, push, force-push, and merge-conflict resolution.

> **Use this skill for any local Kedro check or fix — even single-tool runs like "lint my diff", "run ruff on my changes", or "run one pytest".** Do *not* `pip install ruff` (or mypy, or pytest, or pre-commit) and run them yourself: Kedro's `.pre-commit-config.yaml` and `pyproject.toml` already pin those tools with project-specific configuration, and the right venv must be active. The targeted commands in [reference.md](reference.md) "Fast lint iteration" reproduce CI's results exactly; ad-hoc installs do not.

This skill complements `review-kedro-pr` (judgment-based code review). It does **not** triage PR review comments.

## How to invoke this skill

**Pick a track first**, then run only the steps that track requires. There are two tracks, mapped to the two real situations users hit:

| Track                     | When the user says...                                                                                           | What to do                                                                                                                                                                                                                                                                                                                        |
| ------------------------- | --------------------------------------------------------------------------------------------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| **L. Local dev**          | "babysit my local changes", "verify before push", "run checks locally", "are my changes ready?", "lint my diff" | Step 2 (env) → Step 5a (full sweep to surface FAILs) → Step 4 (per-failure fix loop with targeted commands) → Step 5a (final re-verify) → optional Step 5b (commit + push). **No PR required.** Skips GitHub fetch entirely.                                                                                                      |
| **C. CI diagnosis & fix** | "CI is failing", "fix the lint job", "what's failing on CI?", "fix the X check on this PR", "babysit this PR"   | Step 1 (PR detection) → Step 2 (env) → Step 3 (snapshot via `scripts/watch_ci.sh`) → Step 4 (fix only the failing checks; verify each with the most targeted command — see [reference.md](reference.md) section "Fast lint iteration") → Step 5b (commit + push). **Skip Step 5a** — per-check verify already happened in Step 4. |

### Picking the right track

- **If "babysit this PR" is the only signal**, default to Track C (a PR is implied).
- **If intent is ambiguous**, ask once: *"Verify your local changes before pushing (no PR), or diagnose and fix failing CI on an open PR?"* Pick a track **before** invoking any script.
- **For very narrow Track L asks** ("just lint my diff", "just run ruff on my changes"), skip Step 5a and run the targeted command from Step 4 directly — there's no need for a full-sweep discovery pass.
- **Announce the chosen track in one line before invoking any step** (e.g. *"Picking Track L — no PR signal."*), so the user can redirect.

Each step header below is annotated with the tracks that need it (e.g. `Tracks: L, C`). Skip a step if your track is not listed.

## Workflow

### 1. Identify the PR + preflight _Track: C_

Detect the PR from the current branch, or accept a PR URL/number from the user:

```bash
gh auth status
gh pr view --json number,title,baseRefName,headRefName        # current branch's PR
# or, if the user supplied a PR:
gh pr view <number-or-url> --json number,title,baseRefName,headRefName
```

If the user provided an explicit PR, **thread it through every subsequent command** as `gh pr view <num> ...` and `bash scripts/watch_ci.sh --pr <num>`. The default (no `--pr`) only works for the current branch's PR.

Preflight checks:

- `gh` is installed and authenticated. If not, stop and ask the user to install/authenticate.
- The working tree is clean enough to operate on. Run `git status --porcelain`; if there are uncommitted changes unrelated to the planned fixes, warn the user and ask whether to stash or proceed.
- A PR exists for the current branch. **If no PR exists**, ask the user whether to switch to Track L (local-only) or stop and open a PR first (`gh pr create`); creating PRs is out of scope for this skill.

### 2. Set up the Python environment _Tracks: L, C_

Run `scripts/bootstrap_env.sh`. The script:

- Detects an active isolated env: `$VIRTUAL_ENV` set, OR (`$CONDA_PREFIX` set AND `$CONDA_DEFAULT_ENV != "base"`).
- If no isolated env active: ask the user "venv or conda?" + name. Pass to `bootstrap_env.sh --type {venv|conda} --name <name>`. The script creates the env and prints the activation command. **The skill cannot activate the env from a child shell** — instruct the user to activate and re-invoke the skill.
- If active but dependencies missing: the script runs `make install-test-requirements` + `make install-pre-commit`. **It also runs `make install-docs-requirements` only when invoked with `--with-docs`** — the script does not auto-detect docs files. The agent must determine docs-ness first (see below) and pass `--with-docs` if needed.
- Probes for system tools `vale`, `lychee`, `gh`. Prints platform-specific install hints if missing; does not install them.

**Determining whether to pass `--with-docs`:**

- Track L (no PR exists, so `origin/main` is the default base): `git diff --name-only "$(git merge-base HEAD origin/main)"...HEAD | grep -E '^docs/|\.md$'`. Pass `--with-docs` if there's a match.
- Track C (PR's actual base may differ): `gh pr view --json files -q '.files[].path' | grep -E '^docs/|\.md$'`. Pass `--with-docs` if there's a match.

Read [reference.md](reference.md) section "Environment setup" for manual recipes and cross-platform install hints.

### 3. Snapshot the PR state _Track: C_

Single read-only pass:

```bash
BASE="origin/$(gh pr view [<num>] --json baseRefName -q .baseRefName)"   # resolves the PR's actual base
gh pr view [<num>] --json mergeable,mergeStateStatus,headRefOid,files
bash scripts/watch_ci.sh [--pr <num>]                                    # snapshot CI + dump failed-job logs
git log "$BASE"..HEAD --format='%H %(trailers:key=Signed-off-by)'        # commits since base, with DCO trailer
```

Drop the `[<num>]` / `[--pr <num>]` brackets when operating on the current branch's PR. When the user supplied an explicit PR in Step 1, keep them — omitting the number will silently resolve the *current branch's* PR instead.

Don't hardcode `origin/main` — Kedro PRs may target `develop` or other branches.

Show the user a one-screen summary:

- Mergeable status (`CLEAN` / `BEHIND` / `DIRTY` / `BLOCKED`).
- Failing CI checks, each annotated with the local Make target from [reference.md](reference.md) section "CI-to-local mapping".
- Commits missing DCO `Signed-off-by:` trailer.

`scripts/watch_ci.sh` is snapshot-only: it fetches the current state and exits without blocking on still-running checks. Re-run it later for a refreshed snapshot.

### 4. Fix in this fixed order _Tracks: L, C — sub-bullets gate per track too_

Each sub-step ends with **stop and ask before staging / committing / pushing / amending**.

The Track C sub-bullets (Merge conflicts → CI failures → DCO sign-off) run in that order when multiple apply. Track L only triggers the Local-only failures sub-bullet at the end.

**Merge conflicts** (Track C). If `mergeStateStatus` is `DIRTY` or `BEHIND`, sync with the base branch. Resolve conflicts only when the intent is unambiguous; otherwise stop and ask the user.

**CI failures** (Track C). For each failing check:

1. Look up the local invocation in [reference.md](reference.md) section "CI-to-local mapping" (and the cookbook entry below it for `e2e-tests`, which is intentionally out of scope locally).

2. The failed-job logs were already dumped by `watch_ci.sh` in Step 3. If the snapshot is stale (e.g., new check runs completed since Step 3), re-run `bash scripts/watch_ci.sh [--pr <num>]` for a fresh snapshot — keep the `--pr` flag if the user supplied a PR in Step 1.

3. Propose the smallest scoped fix using [reference.md](reference.md) section "Common CI failures and fixes".

4. Apply the fix to the working tree only (no `git add` / `git commit`).

5. **Verify with the most targeted command available** — almost never `make lint`, which runs *every* pre-commit hook on *every* file plus mypy on the whole `kedro/` package (typically 3–5 min per iteration). Instead:

    - For a single failing pre-commit hook: `pre-commit run <hook-id> --files <changed-files>` (seconds).
    - For ruff/format: `ruff check --fix <file>` or `ruff format <file>` (sub-second).
    - For mypy: `mypy <file> --strict --allow-any-generics --no-warn-unused-ignores` (5–10s vs. 1–2 min).
    - For Import Linter: `lint-imports --config pyproject.toml` (it scans the whole project regardless — but skips pre-commit overhead).
    - For unit tests: `pytest --no-cov tests/path/to/test_thing.py::TestClass::test_method` (sub-second per test) instead of `make test` (~6 min for the full suite + 100% coverage check). **`--no-cov` is required** because `pyproject.toml` always applies `--cov` with `fail_under = 100`, which would otherwise exit non-zero even on a passing single-test run. **Never run `make test` during the fix loop** — pick the failing test path from the CI log and target it directly. **Sandbox: always request `all` permissions when running any `pytest` in this repo** (see [reference.md](reference.md) section "Sandbox & permissions").

    Full per-hook recipes in [reference.md](reference.md) section "Fast lint iteration". Track C does **not** run `scripts/run_local_checks.sh` here.

6. Move to the next finding.

**DCO sign-off** (Track C). List commits without `Signed-off-by:`. Apply one of the recipes from [reference.md](reference.md) section "DCO sign-off recipes" (typically `git rebase <base> --signoff` for older commits). Ask the user before amending; **explicitly warn that amend requires a force-push** (`git push --force-with-lease`).

**Local-only failures** (Track L). Track L drives this loop from the output of Step 5a's full sweep — apply the same targeted-command flow as above for each FAIL.

### 5. Verify locally → commit + push

Two sub-steps. Run the ones your track requires.

#### 5a. Verify locally (full sweep) _Track: L_

```bash
bash scripts/run_local_checks.sh
```

The script auto-detects scope from the changed files (`code`, `docs`, or `code+docs`). It refuses to run if no isolated env is active.

**Local scope is narrower than CI's path filter.** Only `docs/**` changes trigger local docs checks. Generic `*.md` files outside `docs/` (e.g., `RELEASE.md`, root `README.md`) are skipped locally because they don't affect the docs build — but CI's `docs-only-checks` workflow *will* still fire on them. The script prints a one-line note when this divergence applies, with the recommended local pre-check command (`make linkcheck` / `make language-lint dir=docs`). If those checks fail on CI later, Track C is the safety net.

**Before invoking the script, warn the user about the wait time.** Total wall time depends on scope:

- `code` only: **~10–12 min** (lint ~3-5 + test ~6 + detect-secrets ~30s)
- `docs` only: **~5–10 min** (lint ~3-5 + linkcheck ~2-5 + language-lint ~30s)
- `code+docs` (mixed PR): **~12–17 min** (everything above)

**Request `all` permissions upfront** when invoking via a sandboxed shell tool — the script's plan typically includes `make test` and/or `make linkcheck`, which need `all` and `network` respectively (see [reference.md](reference.md) section "Sandbox & permissions").

The script prints the same plan + per-check duration estimates upfront before running, so the user can confirm they're happy to wait or background it. Tell the user to **leave the terminal open** — each check streams output as it runs (`make test` prints per-file dots; `make lint` prints `>>>>>>>> <hook name>` headers).

Show the user the per-check pass/fail/skip summary at the end. Any FAILs feed into Step 4's targeted fix loop — re-run `run_local_checks.sh` only as the final belt-and-suspenders check once all targeted recipes pass.

**Track C skips 5a entirely** — per-check verification already happened in Step 4 for the specific failing checks; running the full sweep would be redundant and slow.

#### 5b. Commit + push _Tracks: L (optional), C_

On user confirmation:

- `git add` only the touched files.
- `git commit` with a message you propose (or the user provides). Use `-s` for DCO sign-off.
- `git push` (or `git push --force-with-lease` for the DCO rebase case — warn explicitly).

On Track L, commit + push is **optional**: the user may just want a clean local working tree before continuing to iterate. Always confirm intent.

After push on Track C, **do not block waiting for CI**. If the user wants to see the new CI state, they can re-run `bash scripts/watch_ci.sh [--pr <num>]` later for a fresh snapshot — keep the `--pr` flag if a PR was supplied in Step 1.

## Out of scope

- **Watching CI to completion (blocking)** — `watch_ci.sh` is snapshot-only by design. The skill surfaces current state and exits; the user re-runs it later if they want a refreshed view. This avoids long blocking sessions where the agent is idle waiting on CI.
- **Running e2e tests locally** — slow, requires packaging the wheel, and rarely needed during the babysit loop. If `e2e-tests` is the failing check, the skill surfaces the CI logs and stops — no local reproduction.
- **Comments triage** — PR review comments, reviewer asks, and bot-generated review feedback (such as Bugbot, the Cursor-style review bot that posts inline comments). The author handles reviewer feedback directly.
- **Judgment-based code review** — defers to `review-kedro-pr`.
- **`RELEASE.md` compliance** — adding or editing `RELEASE.md` entries is a reviewer convention, not a CI check (`gh pr checks` does not surface it). Defers to `review-kedro-pr`, which flags missing entries as Critical.
- **Security review** — defers to a future `kedro-security-review` skill.
- **Authoring features / large refactors** — out of scope; this skill only applies the smallest scoped fix to make a check pass.
- **Performance regressions** — `pipeline-performance-test` (label-triggered on PRs with the `performance` label) reports timing, not pass/fail. The skill surfaces the timing delta and asks the user to investigate manually.
- **Installing system tools** — the skill prints install hints for `vale`, `lychee`, `gh` but never invokes `brew`/`apt`/`cargo` on the user's behalf.