MCP reliability report, 2026-10
Month to date, rebuilt about once a day; the edition is sealed after the month ends. What the remote MCP servers listed in the official registry did when CrawlCheck contacted them: how often they answered the handshake, how fast, and how often their tool lists changed. No tool is ever called and no server is named here.
Partial month: observations start 2026-10-08, when the panel began.
| Endpoints observed | 6,000 of 6,000 in the panel, from 4,985 publishers |
|---|---|
| Observations | 24,624, of which 24,508 answered (99.5%, 95% interval 99.4–99.6%) |
| Asked for credentials | 10,376 of the answered observations |
| Went down | 11 endpoints, 11 times (two failed observations in a row after answering) |
| Time to answer | median endpoint 768 ms; all answers p50 1,075 ms, p95 4,625 ms |
| Tool lists changed | 396 of 3,495 endpoints (11.3%), 508 changes; mean 12.7 tools |
Availability per endpoint
Endpoints with at least 5 observations this month: 1,902. Another 4,098 had fewer, and 0 never answered this month.
| 100% | 1,873 | 98.5% | |
|---|---|---|---|
| 99 to 100% | 0 | 0% | |
| 95 to 99% | 0 | 0% | |
| 80 to 95% | 22 | 1.2% | |
| 50 to 80% | 4 | 0.2% | |
| Under 50% | 3 | 0.2% |
How failed observations failed
| unreachable | 77 |
|---|---|
| http error | 35 |
| redirected | 4 |
Method and limits
each panel member is contacted in rotation from CrawlCheck's network (Cloudflare): initialize, notifications/initialized, tools/list, DELETE session; no tool is ever called. Answered = the handshake completed or the endpoint asked for credentials. Availability per endpoint is answered / observations inside the month.
- one vantage network: an endpoint unreachable only from Cloudflare reads as down
- the panel holds endpoints that answered at least once, so endpoints that never answered are outside it
- endpoints are contacted in rotation, so short outages between two observations are not seen
- no server or publisher is named in this report; per-server readings are in the reliability index
Per-server readings: MCP reliability index. Signed JSON: /api/v1/mcp/reliability/report?month=2026-10.