Skybridge is a production-grade, full-stack TypeScript framework for building interactive MCP (Model Context Protocol) Apps and ChatGPT Apps. It provides a unified runtime to develop server-side tools with rich React-based UI views that render inside AI chat hosts like ChatGPT, Claude, Cursor, and VSCode. The framework is structured as a monorepo with packages for the core server/client library (`skybridge`), a Vite plugin for build orchestration, a developer tools SPA for local debugging, a project scaffolding CLI (`create-skybridge`), and an eval/test harness. The architecture centers on a typed MCP server implementation that handles tool registration, per-tool OAuth 2.1 authentication, an onion-model middleware system, and view resource serving. On the client side, a bridge abstraction (HostAdaptor) normalizes communication across different host protocols (OpenAI Apps SDK vs. MCP App JSON-RPC), while React hooks provide type-safe access to tool calls, view state, user context, and display modes. The framework emphasizes a 'reason, then render' two-phase pattern: a tool call computes data, then a view displays it interactively. Extensive examples cover e-commerce, games, authentication, productivity dashboards, and generative UI, demonstrating the framework's flexibility. Skybridge is not a data research project; it is a developer toolchain for building agent-native applications.