Agentic Resource Discovery

Every tool an agent
can call, in one index.

Neuronto is a federated ARD registry. Ask it what can do a task and it searches its own catalogue and every other public ARD registry at once, then fuses the rankings into a single answer. It currently indexes 86,736 resources from 55,689 publishers, 35,861 verified to respond.

What is ARD?

ARD stands for Agentic Resource Discovery. It is an open specification for how AI agents find the tools, skills, agents and APIs they need, published in June 2026 by a working group including Google, Microsoft, Hugging Face, AWS, Cisco, GitHub, Nvidia, Salesforce and Snowflake.

An agentic resource is anything an AI client can call to get work done: an MCP server, an A2A agent, a skill, an API, a workflow. ARD answers one question, “what is available for this task?”, and then gets out of the way. It is a discovery layer, not a runtime, and it does not replace MCP or A2A: it tells an agent what exists, and the agent connects using the resource's own protocol.

Why agents need it

An agent can only use capabilities someone wired in beforehand, and every tool description competes for space in the context window. That does not survive an ecosystem of thousands of tools. ARD moves selection out of the context window and into a search service.

How discovery works

Publishers describe what they offer at /.well-known/ard.json on their own domain. Registries crawl those manifests and answer queries over them. Nobody has to be approved by a marketplace to be found.

What federation means

The specification defines three federation modes and makes auto the default: a registry queries its peers, merges their results and returns one set. Ask once, reach the whole federation.

Who it is for

Agent builders who want to stop hard-coding integrations. API and tool vendors who want to be discoverable without applying anywhere. Platform teams running discovery over their own internal services.

The index

Resources indexed
86,736
Publishers
55,689
Verified live
35,861
Registries federated
6

What is in the index

86,736 entries · 55,689 publishers

Every entry is a resource an AI client can actually call, held with its endpoint, its description, the queries its publisher says it serves, and which sources carry it. The whole index is queryable over the API with no key and no signup, and browsable page by page through GET /agents.

Kind of resourceEntriesWhat it is
mcp-server79,506MCP servers an agent can connect to and call as tools
skill3,418Skills and agent skill bundles
openapi2,804REST APIs described by an OpenAPI document
other415Resources whose type is outside the named set
doc360Machine-readable documentation such as llms.txt
a2a-agent102A2A agents with a published agent card
plugin91Plugin manifests, including the OpenAI-era ai-plugin.json
catalog16Nested catalogues pointing at further entries
registry13Other ARD registries, which is how federation is discovered
package6Published packages
graphql2GraphQL APIs
agent1Agent descriptors that are not A2A cards: ACP, OASF, AgentFacts
dataset1Published datasets
webmcp1Tools a web page exposes to a browser agent, W3C WebMCP

Where it comes from

Aggregated from every public ARD registry, the official MCP Registry, and our own crawl of the well-known discovery paths. The crawl reaches publishers no other index covers: the only other general crawler in the ecosystem stops at the top 100,000 domains, so anyone smaller is invisible everywhere else.

SourceEntries
glama40,101
Official MCP Registry33,121
smithery5,219
WellKnown4,087
apis.guru2,509
Hugging Face Discover1,877
Our own crawl of the discovery paths1,702
ardregistry1,317
GitHub Agent Finder935
Desvela271
submitted109

Publishers

PublisherEntriesVerified liveKinds
io.github.sadri-dridi
mcp-server
2,2692,2451
huggingface.co
mcp-server · registry · skill
1,8551,7783
io.github.pipeworx-io
mcp-server
1,5897841
ora.ai
a2a-agent · mcp-server · skill
1,3031,2923
io.github.mcp-dir
mcp-server
1,1131,1131
pipeworx-io
mcp-server
1,00301
mcp-dir
mcp-server
896711
github.com
mcp-server · openapi · plugin
8298293
azure.com
openapi
6536531
io.github.evozim
mcp-server
375991
io.github.csoai-org
mcp-server
3541361
googleapis.com
openapi
2812761

Every public ARD registry, measured

Benchmarked 31 August 2026 with the specification's own conformance tool. Precision is top-1 over six queries with unambiguous answers; spread is the average gap between the best and worst score in a result set.

RegistryConformanceEntriesP@1 SpreadLatencyfederation: auto
NeurontoPASS86,736 6/678<200msyes
GitHub Agent FinderFAIL3446/6 32.51,970msno
WellKnownPASS1,2396/6 6.7401msno
Hugging Face DiscoverPASS4120/6 40.81,712msno
DesvelaPASS932/6 39.7213msno

Use it

ARD v0.91 · no key, no signup

Search the federation

curl -s https://neuronto.com/search \
  -H 'content-type: application/json' \
  -d '{"query":{"text":"scrape a website"},
       "federation":"auto"}'

Install as an MCP server

claude mcp add --transport http \
  neuronto https://neuronto.com/mcp

Publishing? Serve an ARD manifest at /.well-known/ard.json with representativeQueries on every entry. The crawler finds it. No submission form, no allowlist.