Claude plays Catan: Managing agent context with Sonnet 4.5

We're introducing new capabilities for managing your agents context on the Claude API. Context editing automatically clears stale tool calls and results from within the context window when approaching token limits, and the memory tool enables Claude to store and consult information outside the context window. Let me show you these capabilities in action with something unexpected. A Game of Catan. Catan is a strategy board game that requires planning over a long time horizon, sharp negotiation skills, and careful observation. Watch as Claude plays against three opponents Ace, Maven and Scout. Claude is building a knowledge base that persists across games, with memory files about each opponent's strategies, like how Maven hoards bricks or Ace has a stockpile of wood. As the game progresses, trades, moves, card draws, and other events accumulate, eventually overwhelming the context. But context editing automatically removes older, less relevant information. After 75 minutes of play, Claude has processed thousands of game events. Yet the context remains clean and focused. These features are now available on the Claude Developer Platform.