Proves guardrails, validators, permissions, hooks, and invariants with controlled pass-fail-pass checks. Use when implementing or reviewing enforcement mechanisms.
Use when recording real session token metrics, tool call counts, retries, and estimated costs per verified task.
Use when designing or evolving REST, RPC, and event schemas with stable contracts, validation, versioning, compatibility, and error schemas.
Use when designing or reviewing HTTP APIs, service interfaces, events, schemas, request/response contracts, and integration boundaries.
Use when evaluating proposed designs against modularity, coupling, data flow, scalability, operational complexity, and existing idioms.
Use when creating end-to-end implementation plans, feature plans, or agentic workflow plans before editing code.
Use for web browsing, QA, and scraping - headless, CLI-driven, no visible window. Fetch page text, screenshot, click, fill forms, assert elements, run accessibility scans.
Use when structuring instructions and context to maximize provider prompt caching and reusing verified findings across session steps.