mcprobe: Skill for Claude Code

Audit an MCP server (MCProbe)

MCProbe scores an MCP server's conformance — how reliably an AI agent can actually use it — across schema quality and behavioral robustness. Reach for it whenever the user wants to evaluate, test, compare, or debug an MCP server.

Pick the path that's available

A. MCProbe is connected as an MCP server (you have probe_* tools). Run the four core tools in order:

1. probe_connect — dial the target: an HTTPS URL, or a stdio command.
2. probe_report — the one-shot audit: lints the schemas, fuzzes behavior, and returns the full report + 0–100 score. (Use probe_lint / probe_fuzz individually if you want just one phase.)
3. probe_disconnect when finished.

B. The mcprobe CLI is available (no MCP tools connected).

# Remote HTTP(S) server
npx mcprobe audit https://example.com/mcp --fuzz

# Local stdio server (the `npx some-server` style)
npx mcprobe audit --stdio "npx @acme/my-mcp-server" --fuzz

# A server that requires an API key
npx mcprobe audit https://api.acme.com/mcp --bearer "$ACME_TOKEN" --fuzz
npx mcprobe audit https://api.acme.com/mcp --header "X-API-Key: $ACME_KEY"

# Machine-readable output (for scripting / CI gates)
npx mcprobe audit https://example.com/mcp --fuzz --json

Omit --fuzz for a fast static (schema-only) audit. Add --json to parse the result programmatically.

Auditing a server that needs credentials

If a target answers 401/Unauthorized, it needs a credential: pass it with --bearer <token> (sends Authorization: Bearer …) or --header "Name: Value" for anything else. MCPROBE_TARGET_TOKEN works instead of --bearer.

Three things to get right:

• Never invent or guess a credential, and never reuse one the user hasn't offered for this purpose. Ask the user for it, and prefer an environment variable over pasting the literal value into a command you echo back.
• --bearer and --token are different keys. --bearer authenticates to the server being audited; --token authenticates to mcprobe.org for push. Passing the MCProbe token as --bearer would hand it to a third party.
• A stdio server takes credentials through its own environment, not these flags — the CLI rejects them for --stdio targets.