What problem does it solve? AI-assisted coding workflows lack a formal way to verify that Claude Code sessions actually accomplish their tasks and that prompt or agent changes do not break existing behavior. This Skill brings eval-driven development (EDD) to Claude Code, treating evals as the unit tests of AI development. ## Core Features & Use Cases - Capability and Regression Evals: Define pass/fail criteria before implementation and verify that changes do not break existing functionality. - Multiple Grader Types: Use deterministic code graders, model-based LLM-as-judge graders, rule graders, or human review depending on the output type. - Reliability Metrics: Track pass@1, pass@3, and pass^3 metrics with recommended thresholds for release-critical paths. - Use Case: Before shipping a new authentication feature built with Claude Code, define capability evals (user registration, login, session persistence) and regression evals (existing routes unchanged), run them, and generate an eval report confirming pass@3 of 100% before merging. ## Quick Start Ask the agent to define an eval for a feature you are about to build, for example: define capability and regression evals for the new authentication feature before writing any code.