A2A Agent Card · Numbers Online

Numbers Online — phone intelligence

Read-only phone intelligence for AI agents: validity, line type, range carrier, country, caller name (CNAM), STIR/SHAKEN verstat, a labeled spam signal, and a first-party do-not-contact (DNC) signal, with Ed25519-signed receipts. Every field is a supplementary, low-confidence signal; the calling agent keeps every routing and dialing decision.

✓ Conformant with A2A 1.0.0. This card passes every structural check in the A2A specification’s AgentCard object — a capabilities object, a declared protocolVersion, and a well-formed skills array.
Provider: Numbers Online Conformance: Conformant Protocol: 0.3.0 Transport: JSONRPC Version: 1.0.0 Host: numbers.online Skills: 4
Discovery

An A2A client finds this agent by fetching the well-known path on the provider's own host. That is what makes an agent card different from every other agent artifact in this catalog: it is provider-published by construction — it cannot be derived, generated, or reconstructed on a provider's behalf.

https://numbers.online/.well-known/agent-card.json
Skills (4)

Phone number intelligence phone_lookup

Return a supplementary, low-confidence intelligence bundle for a phone number: validity, formatting, line type, range carrier, country, caller name (CNAM where available), STIR/SHAKEN verstat, a labeled spam signal, and a first-party do-not-contact (DNC) signal — a suppression preference registered by the number's own owner, never a copy of any government registry. Advisory only.

phonetelephonycaller-idcnamline-typespamdnce164

Line type line_type

Return only the deterministic fields for a number — validity, line type (mobile / fixed line / VoIP / …), range carrier, country, and formatting. Free, fast classification; no paid dip.

phoneline-typecarriere164

Caller risk signal caller_risk

Return a labeled, low-confidence risk read for an inbound caller: a spam signal (0–100, higher = riskier), verstat passthrough, and a first-party do-not-contact (DNC) signal — without a name dip. A supplementary input to the agent's own policy, never a verdict on whether to accept or reject a call.

phonespamriskstir-shakendnc

Do-not-contact supplementary signal dnc_check

Return a first-party do-not-contact signal (suppress / no_match / unknown) for a number, sourced ONLY from suppression preferences registered and verified by the number's own owner inside Numbers Online — never a copy of any government or licensed do-not-call registry. Comes with a signed receipt recording the status "as of T". Advisory only.

phonednctcpasuppressionconsent
Documentation
https://numbers.online/docs
Evidence. Fetched 2026-09-19 from https://numbers.online/.well-known/agent-card.json, HTTP 200. The body was saved verbatim and is the sole source for everything on this page — no field is inferred. View the captured card. Providers change what they serve; if this card has moved or changed shape, the provider profile carries the current state as of the last build.

Work with this as data

Every agent card here is available over the APIs.io API and to AI agents over MCP. A2A Agent Cards 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

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https://apis.io/mcp

Tools for a2a agent cards

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=numbers-online&limit=10"
Everything under a tag
curl "https://apis.io/api/v1/tags/numbers-online"

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