FastCtx

FastCtx gives coding agents structured access to local repositories through MCP. It's an open source Rust runtime for developers who want agents to spend less context on shell syntax and parsing terminal output. It runs on Windows, macOS and Linux under the Apache 2.0 license, with dedicated connections for ChatGPT App and Codex CLI and support for other MCP clients.

Agents can read several text files in one request, inspect images and PDFs, search repository contents, and find files by path pattern. Results include line numbers and explicit indicators of incomplete output, so an agent can distinguish a complete result from one that needs another read. It handles common legacy text encodings as well as UTF-8. Batch replacement supports previews, detects concurrent file changes, and preserves encoding, line endings and file permissions.

Optional Bash tools let agents run commands and manage persistent background jobs, including checking output and stopping process trees. Sessions share a local runtime while keeping their working directories and job-output tracking separate. If that runtime fails, connections can recover without replaying calls that change files or execute commands.

Repository operations run locally without telemetry or runtime network requests. Update checks contact npm and GitHub but don't send file contents, repository paths or job data; Bash commands can make their own network requests. The MCP server uses the host process's local permissions and runs outside the host's filesystem sandbox. Its approval modes can require review of writes and commands, or every tool call.