MCP-TUI
Test, debug and automate Model Context Protocol servers from your terminal.
Point mcp-tui at an MCP server, run any tool from a form built from its input
schema, and get the same call as a CLI command for your CI. When a connection
fails, it tells you why: the HTTP status, the stray line on stdout, the
handshake step the server skipped, and the flag that fixes it.
Install
go install github.com/standardbeagle/mcp-tui@latest
# or
npm install -g @standardbeagle/mcp-tui
Use
mcp-tui --url http://localhost:8080/mcp # TUI
mcp-tui --cmd node --args server.js # a stdio server
mcp-tui --url http://localhost:8080/mcp tool list # CLI
mcp-tui --url http://localhost:8080/mcp tool call search_tickets status=open limit=3
mcp-tui verify http://localhost:8080/mcp # spec and security probes
mcp-tui conform --report-junit conform.xml http://localhost:8080/mcp
Why connections fail, named
A wrong path, the wrong transport, a stdio server logging to stdout, a
server that ignores server/discover, a missing OAuth sign-in: each is
reported with its cause and fix, not as a timeout.
From a manual check to CI
c in the TUI copies the CLI command for a call; Ctrl+E exports the whole
session as a replay script. The CLI prints JSON for jq, refuses arguments
that break the tool's schema, and exits non-zero on tool errors with
--strict-errors.
Conformance for CI
verify probes origin and DNS-rebinding protection, content types, tool
names and list order. conform runs every protocol scenario plus the probes
and writes a JUnit report.
What it covers
| |
|---|
| Transports | stdio, streamable HTTP, SSE (deprecated) |
| Protocol | MCP 2026-07-28 (stateless, multi round-trip requests, list caching) and earlier; --protocol-version pins one |
| Server features | tools with annotations and output schemas, resources and templates, prompts, completion, progress, server logs, tasks, subscriptions |
| Client features | elicitation, sampling and roots, answered in the TUI or from stub flags in the CLI |
| OAuth | client credentials, authorization code with PKCE, dynamic registration, Client ID Metadata Documents, enterprise managed authorization (SEP-990), a token cache |
| Debugging | every JSON-RPC message both ways, HTTP timings, the OAuth flow step by step, credentials masked |
| Config discovery | servers configured for Claude Desktop and VS Code |
Documentation
https://dev.standardbeagle.com/mcp-tui/: how-to guides with recorded runs, error messages, the CLI reference and videos.
Contributing
See CONTRIBUTING.md and ARCHITECTURE.md. The demo videos are recorded from scripts in docs/recordings. Issues and PRs welcome.
License
MIT
