ARD catalog (ai-catalog)

An Agentic Resource Discovery catalog lets agents list the MCP servers, agents, skills and APIs a domain publishes.

Category: Discoverability
Standard: Emerging; Off by default, turn on in settings

1%Top 100 adoption1 of 100 sites implement it 2/9OverviewSpeculativeSpecified, but little evidence anything uses it yet.

Who supports it

GitHub CopilotPartial support
Published 17 Jun 2026 · last checked 9 Oct 2026: Agent finder for GitHub Copilot now availableAgent finder 'implements the open Agentic Resource Discovery (ARD) specification' and searches catalogs you point it at (GitHub's curated catalog or a private registry). No evidence it fetches publishers' /.well-known/ard.json from arbitrary domains.

26 others: no evidence yet. See every agent and browser

What it checks

The extension fetches /.well-known/ard.json, the path the Agentic Resource Discovery (ARD) specification requires, and then /.well-known/ai-catalog.json, the predecessor path that the specification still lets clients read. It uses the first one that returns a non-empty JSON body, and checks that the document parses and has a top-level entries array.

Results

Status	When
Pass	A catalog was found with an `entries` array
Warn	A catalog was served, but it is not valid JSON or has no `entries` array
N/A	No catalog was found at either path

How to fix

If your domain publishes MCP servers, agents, skills or APIs, list them in a JSON document at /.well-known/ard.json. See agenticresourcediscovery.org for the full format.

{
  "entries": [
    {
      "identifier": "urn:air:example.com:mcp:main",
      "displayName": "Example MCP server",
      "type": "application/json",
      "url": "https://example.com/.well-known/mcp/server-card.json"
    }
  ]
}

Once the catalog exists, ARD entry validity checks each entry and ARD trust manifest checks who they are bound to.

Support by agent and browser

Announced means the vendor’s own docs or announcement say so. Published is the date on the vendor’s own page, where it has one. Checked is the last time our weekly research found that page still saying so.

Agent	Status	Source
Coding agents
GitHub Copilot GitHub	Partial support	partial Agent finder for GitHub Copilot now available Published 17 Jun 2026 · Checked 9 Oct 2026Agent finder 'implements the open Agentic Resource Discovery (ARD) specification' and searches catalogs you point it at (GitHub's curated catalog or a private registry). No evidence it fetches publishers' /.well-known/ard.json from arbitrary domains.

No evidence yet26

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Meta AI
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Adoption on the top 100 sites

1 of 100 measured sites implement it

Scanned 23 Oct 2026 with the Sitebulb Labs extension, against the Tranco list (tranco-56Z8N).

9 Oct 2026 1% → 23 Oct 2026 1%

Sites implementing it1

#32 github.com

Overview

2/9

Speculative

Specified, but little evidence anything uses it yet.

How this rating is worked out2 of 9 points

Factor	Points	Why
Vendor support	1 / 3	0 vendors supporting, 1 partly or planned
Top-100 adoption	1 / 3	1% of measured sites
Spec maturity	0 / 3	Community proposal

8 or more points is Established, 5 to 7 is Gaining traction, 2 to 4 is Speculative and under 2 is Stalled. A feature is also Stalled when more vendors have said no than yes. Read the spec.

Community insights

No community insights for this feature yet.

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