Structural grade · AI Catalog 1.0
Flavored
Fails a hard check in the data model. A catalog in spirit rather than in schema.
ARD conformance-test v0.9.1 (ards-project/ard-spec)
PASS
Discovery path
predecessor
Answered only at /.well-known/ai-catalog.json. ARD v0.91 renamed the path to /.well-known/ard.json and made the old one an optional courtesy, so a consumer implementing only the current spec will not find this manifest.
Declared spec version
1.0
The specVersion in the manifest. 1.0 is current for the AI Catalog data model; anything lower is an earlier draft. ARD reads this field as transport-defined and ignores it.
SendHQ API
urn:air:sendhq.cc:api:email
Workspace-scoped REST API for expected outbound and inbound email, verified domains, hosted templates, delivery events, and suppressions.
application/vnd.oai.openapi+json;version=3.1
artifact →
- “send a transactional email from my verified domain”
- “receive replies for a product inbox”
- “inspect bounce and delivery events for an email”
- “publish and send a hosted email template”
SendHQ Email Skill
urn:air:sendhq.cc:skill:email
Instructions for safely operating SendHQ's documented email API and interpreting its outcomes.
- “use SendHQ to send an account verification email”
- “set up a domain and inbound address in SendHQ”
- “check why a SendHQ message bounced”
SendHQ documentation MCP server
urn:air:sendhq.cc:mcp:docs
Read-only tools and resources for SendHQ's public API, authentication, pricing, and integration documentation.
- “how do I authenticate to SendHQ”
- “what does SendHQ cost”
- “find SendHQ documentation for inbound email”
Evidence. Fetched
https://sendhq.cc/.well-known/ai-catalog.json on 2026-09-13, HTTP
200. The verbatim body is stored alongside its manifest in the
SendHQ repository
as
ai-catalog/sendhq-ai-catalog.json. Nothing on this page is derived
or generated: an AI Catalog manifest is served from the publisher’s own domain or it does not
exist, which makes it — like an
A2A Agent Card — one of the few agent artifacts that cannot be
produced on a provider’s behalf. Grades are recomputed on every build; the specification is a
v0.9 draft and
these verdicts will move when it does.
Every descriptor here is available over the APIs.io API and to AI agents over MCP. Agent Discovery is not yet its own endpoint on the v1 API. Reach it through catalog search and the tag graph, or the MCP server.
MCP server
One button, every client — Claude, Cursor, VS Code and the rest.
https://apis.io/mcp
Tools for agent discovery
3 MCP tools reach this
apis_io_searchSTART HERE — APIs, providers and tags for one query, each with its total.
resolveTurn a domain, URL or GitHub org into the provider it belongs to.
find_cohortsEvery scored population of providers in the catalog.
All 92 tools →
Call it yourself
curl for this page
Search the catalog
curl "https://apis.io/api/v1/search?q=sendhq&limit=10"
Everything under a tag
curl "https://apis.io/api/v1/tags/sendhq"
Discovery needs no key. Ratings and market analysis are Pro.
Get an API key
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store it to create your key and to recognise you if you sign in with another
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Terms.
A second provider on the same verified email joins the account you already have.