Context7

Implements an MCP server that exposes documentation resources as tools callable from LLM clients, allowing real-time retrieval of library-specific API docs and code examples directly into prompt context. Uses the Model Context Protocol's resource and tool abstractions to bridge LLM clients with live documentation sources, eliminating the need for manual doc lookups or reliance on training-data-based knowledge.

Maintains an indexed catalog of documentation from multiple library sources (npm, PyPI, official docs, GitHub repos) and maps version specifiers to concrete documentation snapshots. Implements a backend indexing pipeline that crawls and parses library documentation, extracts API signatures and examples, and stores them in a queryable format accessible via MCP tool calls.

Implements a standards-compliant MCP server that exposes documentation tools and resources following the Model Context Protocol specification, enabling seamless integration with any MCP-compatible client without custom adapters. Handles MCP protocol handshake, resource discovery, tool invocation, and response serialization to abstract away protocol complexity from client implementations.

Reduces LLM hallucination by injecting verified, version-specific documentation directly into the prompt context before code generation, ensuring the model has access to authoritative API signatures and examples. Works by intercepting code generation requests, fetching relevant documentation via MCP tools, and prepending it to the system or user prompt with explicit instructions to reference the provided docs.

Extracts working code examples and snippets from indexed library documentation and returns them in context-ready format. Implements parsing logic to identify code blocks in documentation, extract relevant examples for specific functions or patterns, and format them for easy insertion into prompts or generated code.

Validates function calls and API usage against indexed documentation to detect mismatches in function names, parameter counts, types, and required vs optional arguments. Implements schema extraction from documentation (JSDoc, type hints, docstrings) and compares generated or user code against these schemas to flag potential API errors before runtime.

Identifies breaking changes, deprecated APIs, and version migration issues by comparing documentation across library versions and flagging code that uses deprecated or removed APIs. Implements version-to-version diff logic that detects API removals, signature changes, and deprecation notices, then alerts users when their code targets a version where those APIs no longer exist.