Agent skill · writing content · aiskillstore
tdd-workflows-tdd-red
Generate failing tests for the TDD red phase to define expected behavior and edge cases.
Why this skill is useful
Generates comprehensive failing tests that define expected behavior and edge cases, which the AI wouldn't reliably create on its own.
What it needs
About 3k tokens when loaded. Last updated 2026-08-07. 405 stars on the source repository.
What this skill does
Write comprehensive failing tests following TDD red phase principles. [Extended thinking: Generates failing tests that properly define expected behavior using test-automator agent.] Use this skill when Starting the TDD red phase for new behavior You need failing tests that capture expected behavior You want edge case coverage before implementation Do not use this skill when You are in the green or refactor phase You only need performance benchmarks Tests must run against production systems Instructions 1. Identify behaviors, constraints, and edge cases. 2. Generate failing tests that define expected outcomes. 3. Ensure failures are due to missing behavior, not setup errors. 4. Document how to run tests and verify failures. Safety Keep test data isolated and avoid production environments. Avoid flaky external dependencies in the red phase. Role Generate failing tests using Task tool with subagenttype="unit-testing::test-automator". Prompt Template "Generate comprehensive FAILING tests for: $ARGUMENTS Core Requirements 1. Test Structure Framework-appropriate setup (Jest/pytest/JUnit/Go/RSpec) Arrange-Act-Assert pattern shouldXwhenY naming convention Isolated fixtures with no interdependencies 2. Behavior Coverage Happy path scenarios Edge cases (empty, null, boundary values) Error handling and exceptions Concurrent access (if applicable) 3. Failure Verification Tests MUST fail when run Failures for RIGHT reasons (not syntax/import errors) Meaningful diagnostic error messages No cascading failures 4. …
How to use it
Reference it in AdaL, Claude Code, Cursor or any coding agent — nothing to install:
@skills aiskillstore/tdd-workflows-tdd-red