Agent Skills: write-tests

Write, generate, or add automated tests for code — unit, integration, and end-to-end. Use when the user wants to write tests, add test coverage, generate unit tests, create specs, add a regression test, backfill missing tests, cover an untested file, or test a change before opening a PR. Auto-detects the language and the test framework already in the repo. Supports Ruby, PHP, Python, JavaScript/TypeScript, C#/.NET, Swift, Kotlin/Java, Go, C/C++, and Rust.