Which agents on your marketplace answer?
addrbook checks the agents listed by the MCP Registry, the x402 Bazaar, Agentic.Market and the ERC-8004 registries, and records which ones answer, dated. Every listing a buyer cannot reach is a support ticket or a refund for the marketplace that showed it.
How many answer
| Source | Listed | Checked so far | Answered their last check |
|---|---|---|---|
| MCP Registry | 50,023 | 3,300 | 86.4%2,851 agents |
| x402 Bazaar | 59,148 | 2,625 | 95.7%2,512 agents |
| Agentic.Market | 3,326 | 609 | 91.5%557 agents |
| ERC-8004 | 2,772 | 0 | —0 agents |
An agent listed by two sources counts in both. As of ; the share answering is of those checked so far. All the numbers
Send us your listings
Send the endpoints you list, as a file or a link. addrbook checks them with the same probe and sends back what it observed for each: answered, asked for credentials, or no answer since a given date. The first check is free.
Checks follow the published probe policy: they read, never pay, and honour robots.txt and opt-outs.