HighPR-scope

Call out breaking changes explicitly

If an API/contract or behavior is breaking, add a 'BREAKING CHANGE' section detailing what breaks, migration steps, and affected consumers.

Why this matters

Explicit warnings prevent downstream failures and accelerate coordination.

Side-by-side examples engineers can pattern-match during review.

Avoid

Changed response shape silently.

Prefer

BREAKING CHANGE: /v1/users no longer returns 'age'.
Migration: read 'birthDate' instead.
Consumers: mobile v2, web app.

Bad

Refactor without noting breakage

Good

Dedicated BREAKING CHANGE section

From the same buckets as this rule.

High
Avoid mixed concerns in one PR
Do not combine mechanical changes (formatting, renames) with behavioral changes. If unavoidable, separate commits and call out which commits are mechanical.
pr-hygienereadability-refactor+1
High
Behavioral changes must add or update tests
If files under src/ change behavior, the PR must include tests/ updates or a PR description line no-tests: <reason> explaining why tests are unaffected.
testing-qualitypr-hygiene
High
Bugfix PRs must match the real production failure (root cause, not band-aid)
If the PR claims to fix a specific issue (e.g., 'Fixes #123' / 'Fix PAY-123'), validate it against the real production error. - If an observability MCP is available (Sentry/Datadog/Bugsnag): fetch the event/stack trace and confirm the change addresses the root cause. - Require a regression test (or a clearly documented reason why a test cannot be added). Call out fixes that only hide symptoms (catch-and-ignore, broader retries, defaulting values) without removing the underlying failure mode.
pr-hygieneerror-handling+2