Cycles is an open protocol and runtime for enforcing hard limits on agent spend, risk, and actions before execution. Instead of relying on dashboards or alerts after something goes wrong, Cycles lets teams stop the next model call, tool call, or side effect before it happens. Built for autonomous systems, open source under Apache 2.0, and works across modern AI stacks with multi-language SDKs: Python, TypeScript, Java, Rust. Integrations with: LangChain, OpenClaw, OpenAI, Anthropic and more.