FileMCP
A native desktop app for macOS and Windows that gives ChatGPT controlled access to a local workspace through MCP, reading and modifying files, running git operations and, when explicitly enabled, local shell commands.
FileMCP runs a local MCP server bound to the loopback address and uses a secure MCP tunnel to make it reachable by supported OpenAI products without opening a public inbound port. Built-in filesystem tools are restricted to one configured workspace root, with symlink and canonical-path checks protecting that boundary, and git operations are available without enabling arbitrary shell execution, which stays off by default.
The app has native implementations on both platforms, Swift and AppKit on macOS, C# and .NET 8 with WPF on Windows, sharing an equivalent core MCP surface: filesystem, git, Codex-history import, the protocol, the tunnel, and optional command execution. Runtime API keys are stored in the OS credential store, and process output, request size, search scope and concurrency are all bounded, with descendant processes cleaned up on timeout or shutdown.
It is an independent open-source project, not an official OpenAI product, written in C# and licensed under Apache-2.0.