Public MCP reliability index: every remote server in the official MCP Registry that has answered the handshake, re-observed in rotation (panel.per_hour endpoints an hour; panel.each_seen_every_hours says how often each is contacted). No parameters: the ranked index (availability, p50/p95 ms, tool-list drift over 14 days, per server and per publisher). ?url= one server with its observation history and incident_history (incidents bounded between observations, blips, tool-list changes, uptime by UTC day), signed. ?host= one publisher's servers, signed. No tool is ever called.