`drift check`

Evaluates your codebase against your documentation to detect out-of-sync content based on your .drift.yaml configuration.

Basic Usage

Check all tracked files:


drift check

Use a custom configuration file:


drift check --config /path/to/custom/drift.yaml

Advanced Checking

Check Changed Files (Action/CI)

For lightning-fast CI/CD pipelines, verify only files that have changed in an active pull request:


# Pass explicitly modified files
drift check --changed-files "pkg/server/main.go,docs/api/server.md"

Combined with git to seamlessly automate pull request checks:


# Get PR files and pass them directly to Drift
CHANGED_FILES=$(git diff --name-only origin/main...HEAD | tr '\n' ',')
drift check --changed-files "$CHANGED_FILES"

See our CI/CD Integration guide for more information and GitHub Actions examples.

Diff-Aware Strictness (`--diff-only`)

By default, Drift is strict. It will fail if any drift exists in the evaluated files, even if that documentation debt is years old.

To seamlessly integrate into legacy codebases without blocking PRs, use --diff-only. This mode evaluates the exact git diff. It will only fail if the LLM determines your new code changes directly caused the documentation drift. Legacy drift is reported as a soft warning.


# Forgive legacy documentation debt, but block new drift
git diff origin/main...HEAD > pr.diff
drift check --changed-files "$CHANGED_FILES" --diff-only --diff pr.diff

Example Output

If Drift detects discrepancies, it exits with a non-zero code to block your pipeline and provides the LLM’s explicit reasoning:


Loaded 1 rules from .drift.yaml (provider: gemini)
  - Rule: User API
    Found 1 code files, total size: 1234 bytes
    Found 1 doc files, total size: 567 bytes
    Result: Out of Sync (Reason: The `GetUser` function in `user.go` now includes a `context.Context` parameter, which is not reflected in the `users.md` documentation.)
Drift detected

drift check