Evans vs grpcui

Evans is a free universal gRPC client for manual API inspection and scripting on Linux, macOS, and Windows. Its interactive REPL completes package, service, and RPC names. Stateless CLI mode reads standard input or files and prints JSON-formatted results. When server reflection is enabled, Evans can use that instead of proto files. It supports client-streaming, server-streaming, and bidirectional-streaming RPCs, plus gRPC-Web; TLS is not supported for gRPC-Web. The listed IDL and codec is Protocol Buffers 3, and the compressor is GZIP. For ordinary gRPC connections, the project documents secure TLS connections with the --tls option. Installation options include GitHub Releases, Homebrew, Docker, and Go, with Releases or Homebrew recommended for automatic updates. The documented Go installation requires Go v1.20 or later. The repeat option does not support client-streaming or bidirectional-streaming RPCs. Evans uses the MIT license.

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.