Public AI agents and their reachability

Public MCP and A2A agent endpoints from the official MCP Registry and the A2A Registry, placed by hosting location (cloud region or approximate city; edge-hosted endpoints are counted but not placed), with the hourly reachability check (one HTTPS request per host; any answer below 500 counts as reachable). Also the requests agents send to ShadowGraph (city-level, no IP addresses stored; own tests excluded) and per-step counts for the last 7 days.