Overview and Philosophy

Claude Code combines a terminal UI with an AI backend and a thoughtfully designed tool system. Its architecture addresses four key challenges:

  1. Instant results: Uses async generators to stream output as it's produced.

    // Streaming results with generators instead of waiting
async function* streamedResponse() {
  yield "First part of response";
  // Next part starts rendering immediately
  yield await expensiveOperation();
}

  2. Safe defaults: Implements explicit permission gates for file and system modifications.

  3. Extensible by design: Common interface patterns make adding new tools straightforward.

  4. Transparent operations: Shows exactly what's happening at each step of execution.

The result is an AI assistant that works with your local development environment in a way that feels fast, safe, and predictable.