ProtoPeek is a local-first, open-source workbench for inspecting gRPC and HTTP services. It runs a local Go process with a browser-based console and command-line entry points.
The gRPC workspace supports reflection, proto and protoset schemas, unary and streaming calls, metadata, headers, trailers, and response inspection. The HTTP workspace supports request editing, cancellation, response inspection, and local history.
Network tools provide DNS and kernel-route context, bounded private-network discovery, a logical topology notebook, and offline Nmap XML import. Active hop probing is supported on Linux; it is not offered on Windows or macOS.
The v0.5.0 release also includes a local HTTP(S) downloader using a separately installed aria2c. ProtoPeek is available for Windows, macOS, and Linux.