Sutra

This is a cognitive toolkit that gives Claude structured reasoning patterns and memory primitives. Instead of just prompting differently, you get actual tools: thinking models like backtracking and symbolic abstraction, memory cells for state and episodic storage, and multi-agent patterns like debate councils. The Gateway tool routes requests to either direct execution or the Architect, which generates custom agent blueprints by combining these primitives. The Librarian exposes a browsable catalog of all available techniques. Useful when you need more than conversation history, like maintaining state across sessions, enforcing verification steps, or orchestrating multiple reasoning perspectives on complex problems.