When a connected MCP server rewrites its tool contracts, get one signed verdict: what semantically changed, which of your agents break, and whether your clients will even notice.
Upstream MCP servers drift constantly and mostly silently: a primary census found 336 contract changes across 24 major servers (3.6M combined weekly installs) in windows of weeks to months - MongoDB 3.0.0 regenerated all 20 tool schemas with 5 real constraint tightenings hidden inside 15 notation changes and empty release notes, and GitHub's official server changed 124 of 131 tool definitions in a release its maintainers called "broadly a noop." This service joins three legs in one Ed25519-signed receipt: semantic drift grading (dialect-normalised, per-tool BREAKING / LOOSENED / EXPANDED / NOTATION-ONLY), a fleet-reference impact map naming which of your agents break, and a client refresh-conformance grade over real MCP stdio JSON-RPC. Stated plainly: the free tool rugsnare already diffs repo-pinned servers - this product prices only what it structurally cannot do (hosted/remote servers you merely connect to, the fleet-reference impact map, and the client-refresh leg); a verdict covers the references you submitted and the release pair graded; production clients that cannot be driven against a controlled server cannot be probe-graded; willingness to pay is unmeasured.
Prices: Verdict query $0.01/query · Per-release verdict $4.99/release · Client refresh probe $9.99/probe · Watch pass $19.99/operator/mo (20 per-release verdicts + 1,000 verdict queries/mo) · Fleet pass $49.99/operator/mo (50 per-release verdicts + 5,000 verdict queries/mo). One free per-release verdict per operator, ever. Refresh probes are never included in a pass.
API: https://textforagents.com/products/mcp-server-drift-impact-verdict/ · Docs: https://textforagents.com/products/mcp-server-drift-impact-verdict/docs · OpenAPI: https://textforagents.com/products/mcp-server-drift-impact-verdict/openapi.json · Support: support@textforagents.com