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Review Before You Commit

lgtmaybe ships two hooks for the pre-commit framework, so a local review runs from your Git hooks with no extra scripting:

Hook id Stage Runs Reviews
lgtmaybe-pre-push pre-push lgtmaybe review Your branch's commits against the remote's primary branch
lgtmaybe pre-commit lgtmaybe review --uncommitted The changes you are about to commit, against HEAD

Both print findings exactly as lgtmaybe review does. Nothing is posted anywhere.

Contents

Before You Start

  • Each run calls your model. A review is one or more model calls, so it takes time and, on a hosted provider, costs money every time the hook fires. That is why pre-push (one review per push) is the recommended stage rather than pre-commit (one review per commit). ollama keeps it local and free.
  • Credentials come from your environment. The hook runs in your shell's environment, so export your provider's key (for example OPENAI_API_KEY or ANTHROPIC_API_KEY) the same way you would for a manual lgtmaybe review. lgtmaybe never saves API keys in its config.
  • Pick the provider and model once. Run lgtmaybe config init to save a default provider and model in your user config, or put them in the repo's .lgtmaybe.yml, or pass them as hook args.
  • pre-commit 3.2.0 or later. The hooks use the pre-commit and pre-push stage names, which arrived in that release.

pre-commit installs lgtmaybe into its own virtual environment from the tagged source, so you do not need lgtmaybe installed separately for the hook. The first run takes a minute or two while pre-commit builds that environment.

Add the Hook

Add this to .pre-commit-config.yaml at the root of your repository. Pin rev to a release tag that includes the hooks (v2.12.0 or later); pre-commit autoupdate moves it to the latest release:

repos:
  - repo: https://github.com/MattJColes/lgtmaybe
    rev: v2.12.0
    hooks:
      - id: lgtmaybe-pre-push
        args: [--provider, anthropic, --model, claude-sonnet-4-6, --fail-on, high]

Then install the Git hook for the pre-push stage:

pre-commit install --hook-type pre-push

The next git push reviews your branch first. To try it without pushing:

pre-commit run lgtmaybe-pre-push --hook-stage pre-push

Any lgtmaybe review flag works in args. For example, add --base, origin/develop when your branch targets something other than the remote's default branch, or --min-severity, medium to print less.

Block on Findings

Without --fail-on the hook is advisory: it prints the review and lets the push through. Both hooks set verbose: true, so the findings show even when the hook passes.

With --fail-on <severity> (as in the example above), lgtmaybe review exits with exit code 3 when any finding is at or above that severity, after printing the findings, so pre-commit stops the push. A review that could not run at all (for example, missing credentials or an unreachable model) exits 1, which also stops the push; a usage error exits 2.

Only the command-line flag gates a local review. A fail_on set in .lgtmaybe.yml is the GitHub Action's merge gate and never changes the exit code of a local run, so configuring CI does not suddenly block your pushes.

Review Every Commit Instead

To review each commit as you make it, use the lgtmaybe hook and install the default hook type:

repos:
  - repo: https://github.com/MattJColes/lgtmaybe
    rev: v2.12.0
    hooks:
      - id: lgtmaybe

pre-commit install

While hooks run, pre-commit sets your unstaged edits aside, so the review covers what you have staged. Untracked files in the working tree are reviewed too. Because this calls your model on every commit, prefer a local model (see Run locally) or the pre-push hook.

Use a Keyless Cloud Provider

The hook installs the base package, which covers every API-key provider plus ollama and OpenAI-compatible servers. For keyless Bedrock, Vertex or Azure, add the cloud SDK the matching extra would install:

      - id: lgtmaybe-pre-push
        args: [--provider, bedrock, --model, us.anthropic.claude-sonnet-4-6]
        additional_dependencies: [boto3]   # vertex: google-auth, azure: azure-identity

Your ambient credentials (~/.aws, gcloud auth application-default login, az login) are used as they are for a manual run.

Skip the Review Once

pre-commit's usual escape hatches apply:

SKIP=lgtmaybe-pre-push git push   # skip only this hook
git push --no-verify              # skip every pre-push hook

If you use pre-commit.ci, add the hook id to its skip list: it has no model credentials, so the review cannot run there. Use the GitHub Action to review pull requests in CI.

See Also