MCP Uptime
← MCP Reliability Index  /  Web & Scraping
L

Litmus

io.github.polygraphso/litmus
Grade MCP servers A to F with the open behavioral litmus. npm: full toolset; hosted: lookups only.
healthy
status
3
tools exposed
3622ms
connect latency
a14d50b53808
schema fingerprint

Tools (3)

check_server
Read a server's published behavioral grade (A-F) from polygraph.so in under a second; no execution. The pre-flight check before recommending or installing an MCP server. On a miss it returns not_available (unevaluated: neither safe nor unsafe) with next steps.
list_servers
Servers with a published polygraph grade, sorted A-first then by ref. Returns up to `limit` rows starting at `offset` (default limit 25, capped at 100 per call); `grade` restricts to one letter. `summary` always covers the full graded corpus (a total plus a count per grade), regardless of `grade`, `
request_grade
Record a grade request with polygraph.so. Recording is free; only real, plausibly-MCP targets are accepted. Grading starts once the request's one-time $1 USD fee is paid: payment.payUrl is the human/browser checkout (paid in $POLYGRAPH), and payment.x402Url is the agent rail, POST the same request b

Endpoint

https://polygraph.so/api/mcp
Category: Web & Scraping · Last checked: 2026-08-15T10:10:21Z

Monitor your own MCP server

Get alerted the moment yours goes down, a tool schema drifts, or an upstream silently breaks.

Get early access
How we measure →
What this means. This server responded to the MCP handshake and listed its tools without authentication. The schema fingerprint lets us flag if tool signatures silently change (schema drift) between checks.