Numbers Online — Phone Intelligence
@numbers-online
A hosted, read-only Model Context Protocol server that gives an AI voice agent phone intelligence in one call — who is this inbound caller, and is this number one to think twice about — before it burns agent minutes. Four read-only tools: phone_lookup (validity, line type, range
Overview
What is Numbers Online — Phone Intelligence?
Numbers Online — Phone Intelligence is a hosted, read‑only Model Context Protocol (MCP) server that provides phone intelligence to AI voice agents. It validates inbound caller identity and outbound number risk in a single API call before agent minutes are spent. The server is remote – no installation or local runtime is required.
How to use Numbers Online — Phone Intelligence?
Point any MCP client (Claude Desktop, Claude Code, IDEs, Vapi, Retell) at the Streamable HTTP endpoint https://numbers.online/api/v1/mcp with an API key in the Authorization header for tool calls. Discovery (tools/list) works without auth. Use tools like phone_lookup, caller_risk, line_type, or dnc_check by calling them with a phone number argument.
Key features of Numbers Online — Phone Intelligence
- Four read‑only, idempotent tools:
phone_lookup,caller_risk,line_type,dnc_check - Remote / Streamable HTTP transport – nothing to install or run
- Bundled billing for full lookups;
line_typeanddnc_checkare free - First‑party, consent‑first do‑not‑contact signal (not a government registry copy)
- Signed receipts for verifiable “checked as of T” evidence
- Raw phone numbers are never stored – only SHA‑256 hashes
Use cases of Numbers Online — Phone Intelligence
- Real‑time caller identification and risk assessment before answering an inbound call
- Validating outbound numbers (line type, carrier, country) before dialing
- Checking a first‑party do‑not‑contact preference before placing a call
- Obtaining a signed, verifiable receipt that a number was checked at a point in time
FAQ from Numbers Online — Phone Intelligence
How does the DNC signal differ from government Do‑Not‑Call registries?
The DNC signal is first‑party: it reflects a do‑not‑contact preference registered and verified by the number’s owner inside Numbers Online. It is not a copy or replica of any government or licensed do‑not‑call registry.
What runtime or dependencies are required?
None. The server is hosted – just point your MCP client at the provided endpoint URL. No software to install, no local processes to run.
Where do phone numbers and lookup results live?
Raw phone numbers are never logged or stored; they are hashed (SHA‑256) for privacy. Signed receipts contain only the hash and can be fetched without an API key. The MCP path is read‑only and stateless.
What are the known limits of the server?
Every output is an advisory, low‑confidence supplementary signal. The calling agent keeps all routing and dialing decisions and remains responsible for compliance. Nothing asserts that a call is lawful, unlawful, “safe”, or “spam”. Reassigned‑number status is intentionally not offered.
How do I authenticate and which transport is used?
Transport is Streamable HTTP (JSON‑RPC 2.0) at https://numbers.online/api/v1/mcp. Discovery (tools/list) is public; all tool calls require an Authorization: Bearer <api_key> header with an mcp‑scoped key.
