grpcmd vs grpcui

grpcmd is a free command-line tool for working with gRPC services on Linux, macOS, and Windows. It can use reflection to find available services and methods, describe a method’s request and response messages, and make calls. Requests and responses can stream, with headers, data, and trailers included in output. Users who do not want to rely on reflection can instead provide.proto files and import search paths. The tool can also start a gRPC server implementing grpcmd.GrpcmdService with reflection, and its documentation covers shell completion for Bash, Zsh, fish, and PowerShell. A related tool, grpcmd-script, lets users define endpoint tests in JavaScript and assert response headers, data messages, and trailers; it is distributed as a binary and does not require Node.js. The separate grpcmd-gui desktop app supports reflection-based method lookup, request headers, response headers and trailers, JSON request templates, streaming, and themes. GUI downloads are available for macOS, Windows, and Linux, including amd64 and arm64 builds. grpcmd is listed at free; grpcmd-script is listed at $9 a year with early-bird pricing.

grpcui is a free, open-source command-line tool for interacting with gRPC servers through a browser-based interface. It is aimed at gRPC APIs rather than REST APIs and can discover service schemas through server reflection, .proto source files, or compiled protoset files. Its interface builds dynamic forms for protobuf messages, including well-known types, oneofs, and maps, and also accepts a complete JSON request body. grpcui supports RPC methods including streaming, then displays response headers, messages or errors, trailers, and readable HTML tables. It connects to plaintext and TLS servers, including mutual TLS with client certificates. Streaming requests have a constraint: they must be constructed all at once, so bidirectional streams cannot be handled interactively like they can with grpcurl. The project also provides Go packages for embedding a form or complete web UI in a Go HTTP server. Installation is documented through Homebrew on macOS or Linux, and through the Go install command. It is released under the MIT license.