# AI Catalog well-known file

[1 · Discover](/category/discover/)

| AI Catalog well-known file |
| --- |
| Category | [Discover](/category/discover/) |
| Part of | [Agentic Resource Discovery](/protocols/ard/) |
| Governed by | ARD / ards-project (see ard) |
| Status | Deprecated predecessor path of the ARD manifest |
| Phase | withdrawn |
| Implementation | deprecated |
| Adoption | unmeasured |
| Version | n/a -- not a separately versioned artifact |
| Specification | [https://raw.githubusercontent.com/ards-project/ard-spec/main/spec/ard.md](https://raw.githubusercontent.com/ards-project/ard-spec/main/spec/ard.md) |
| Found at | /.well-known/ai-catalog.json |
| Last checked | 2026-09-06 |

[Discover](/category/discover/) This record modelled the /.well-known/ai-catalog.json well-known file as if it were a distinct, separately maintained artifact alongside the ard record. Reading the ARD v0.91 specification text directly [[1]](#ref-1) shows this is incorrect: ai-catalog.json is the same lineage as ARD -- it is explicitly named in the current spec as "ARD's predecessor" path, kept only as an optional legacy fallback that a conformant ARD consumer is not required to read. There is no independent governance, schema, or spec document for ai-catalog.json distinct from the ARD project; it is a prior version of the same well-known manifest concept, now superseded by /.well-known/ard.json.

## Overview
Keeping this as a separate map entry created a false impression of two competing discovery mechanisms. All content that was useful here (its role as the file most publishers currently serve, per our probe evidence) has been moved into the ard record's summary and dispute fields, where the version history and the adoption lag it represents can be read together. This record is marked withdrawn rather than deleted so the id remains resolvable and the merge history is auditable; readers of agenticweb.wiki should be pointed to ard instead.

## Discovery and probe

superseded -- see ard · /.well-known/ai-catalog.json

```
GET https://{origin}/.well-known/ai-catalog.json
parse:     superseded; see the ard record's probe for the current canonical path
on absent: superseded; see ard
```

Live check run by [the MCP probe](/mcp/server-card): GET /.well-known/ai-catalog.json. Deprecated predecessor path of the ARD manifest, still probed so the census can count migration.

```
{
 "path": "/.well-known/ai-catalog.json",
 "expect": {
  "json_keys": [
   "entries"
  ]
 },
 "note": "Deprecated predecessor path of the ARD manifest, still probed so the census can count migration."
}
```

## History
- 2026-09-05 — seeded from Exa Agent research run
- 2026-09-06 — merged into ard: confirmed via ARD v0.91 spec text that ai-catalog.json is ARD's own deprecated predecessor path, not a separate specification
- 2026-09-06 — fix round 1: added second evidence entry (Google ARD launch blog post, fetched directly) to satisfy the two-evidence gate

## Instances

- [agenticweb.wiki](https://agenticweb.wiki/.well-known/ard.json) · Observed 2026-09-06 · site

Every instance with its source is listed on the [instances page](/instances/).

Our probe: seen on 31 of 50 probed origins, last 2026-09-04. Probed origins are whoever was asked about, not a sample; the count is a floor.

## See also

- Part of: [Agentic Resource Discovery](/protocols/ard/)

- [Well-known URI](/terms/well-known/)

## References

- ARD v0.91 names /.well-known/ai-catalog.json as its own predecessor path, not a separate specification: "ARD's predecessor specified the path /.well-known/ai-catalog.json and the link relation ai-catalog; a consumer MAY additionally consult these." — [https://raw.githubusercontent.com/ards-project/ard-spec/main/spec/ard.md](https://raw.githubusercontent.com/ards-project/ard-spec/main/spec/ard.md) (2026-08-26) VERIFIED
- Google's own launch post for ARD instructs publishers to host an ai-catalog.json file at a well-known path on their domain as step 1 of the four-phase discovery flow, confirming this well-known file is ARD's original (now-predecessor) publishing mechanism rather than a separate specification. — [https://developers.googleblog.com/en/announcing-the-agentic-resource-discovery-specification/](https://developers.googleblog.com/en/announcing-the-agentic-resource-discovery-specification/) (2026-06-17) VERIFIED

[JSON](/data/protocols/ai-catalog-well-known-file.json) · [Markdown](/protocols/ai-catalog-well-known-file/index.md)