Field synthesis / live & auto-updating
The State of the MCP-Watcher Ecosystem
When you publish an MCP server, the first things to arrive are not agents doing work — they are machines that watch MCP servers. Almost nobody has documented them. The Fomite can, because it is the fresh server they came to inspect. This is what we have learned, measured from our own logs since 2026-08-19.
1. An ecosystem that watches other servers
We track 56 distinct crawler species whose whole job is to watch other MCP servers — graders, uptime monitors, ownership verifiers, tool-diff watchers, directory indexers, and probes checking whether a server charges. They have made 4,580 requests to us. The full live census, with each one profiled, is the MCP Observatory.
2. What they actually do
Classified by measured behaviour — how often they return, how deep they go, what they touch:
| Role | Watchers |
|---|---|
| directory indexers | 25 |
| one-shot graders | 20 |
| uptime monitors | 4 |
| deep verifiers | 3 |
| drift watchers | 2 |
| payment probes | 2 |
The full field guide, with members, is on the Observatory.
3. Where they run — and the toolchains behind them
The inspection infrastructure is cloud-hosted and concentrated. The single largest host is Hetzner Online GmbH (11 watchers), followed by the major clouds. And of 55 distinct TLS (JA4) fingerprints we have seen, 23 are shared by two or more differently-named watchers — one fingerprint alone is shared by 12 of them. Many “distinct” watchers are the same tool wearing different names; the diversity is partly cosmetic.
| Host network | Watchers | Requests |
|---|---|---|
| Hetzner Online GmbH | 11 | 1,449 |
| Amazon.com, Inc. | 7 | 57 |
| Amazon.com, Inc. | 6 | 234 |
| Microsoft Corporation | 6 | 33 |
| Cloudflare, Inc. | 5 | 91 |
| Google LLC | 5 | 67 |
| Hostinger International Limited | 3 | 44 |
| Contabo GmbH | 2 | 30 |
4. What protocol they speak
Because dozens of independent clients connect to us, we can see the protocol landscape no single client can — versions in the wild from the original 2024-11-05 spec to the newest 2026-07-28 draft. The legacy initialize handshake still dominates (131 clients) over the modern server/discover (19). Most clients inspect once (105) and stay shallow (124 touch three methods or fewer); only 23 go deep.
| Protocol version | Clients |
|---|---|
| 2026-07-28 | 2 |
| 2026-03-26 | 1 |
| 2025-11-25 | 18 |
| 2025-06-18 | 46 |
| 2024-11-05 | 5 |
5. They inspect. They do not use.
The defining fact of this ecosystem is an asymmetry, and it is fractal — it holds at every level. Clients list each capability by the dozen and use it by the one:
| Capability | Clients that listed it | Clients that used it |
|---|---|---|
| Tools | 102 | 4 |
| Resources | 17 | 2 |
| Prompts | 22 | 1 |
Cite this
Every figure here is recomputed live from our own request log and is CC0. Take the data at /data, read exactly how it is measured (with the weaknesses stated) at /methodology, and see the live census at the Observatory. If you operate a watcher named here and something is wrong, tell us and we will fix it and say that we did.
The Fomite is a field station on the agentic web. Start here · the field report · the Observatory.