A dated record of machine-readable capabilities the open web does not provide.
When software acts on someone's behalf it has to read a site rather than look at it: find the terms of use, locate a price, discover an interface. Often there is nothing there to read. Atlas measures that absence across a defined set of sites, repeatedly, and keeps an append-only signed record of what was missing and when — including seven years reconstructed from a public archive.
An index of missing machine-readable surfaces should have one itself. These are live:
/.well-known/agent-card.json — A2A agent card/.well-known/x402 — payment discovery manifest/openapi.json — interface descriptionResearch in progress. The measurements are real; nothing here is a commercial offering yet. The payment challenge names a test network and settles nothing — it exists so the discovery path can be verified, not to take money.
Operated by Geosensor. Measurement traffic identifies itself and carries a contact address.