coverage-gaps

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name: coverage-gaps description: Find the untested code paths that actually matter, not just the coverage percentage. Use after adding tests. when_to_use: "improve coverage", after writing tests, pre-merge quality check

Coverage Gaps

Coverage % is a vanity metric. Hunt the gaps that bite:

• Error paths — the 500, the timeout, the empty/null input, the malformed payload. Almost always untested.
• Boundaries — 0, 1, max, off-by-one, empty collection.
• Branches — every if/else and catch exercised, not just the happy line.
• Concurrency / order — anything stateful tested in isolation AND in sequence. Skip tests that assert a constructor sets a property — worthless. Test behavior, not implementation. Output: the 3-5 highest-risk untested paths, ranked by blast radius, with the test to add.