npiwho

npx add-mcp 'https://npiwho.com/mcp'

MCP server

NPI Who is available to AI assistants over the Model Context Protocol. The endpoint is https://npiwho.com/mcp (Streamable HTTP). It is free and needs no key. Every result that names a provider or facility starts with the public page's URL, so an assistant can cite the page it answered from and send readers there for the detail. The tools give the headline facts; the pages give the figures.

Connect

Nothing is installed by this page. Each client keeps its own list of MCP servers, so add the endpoint once in the client you use, then start a new conversation; the server does not appear in a conversation that was already open. There is no account and nothing to sign in to.

Claude Code (terminal). Run this once, in any directory:

claude mcp add --transport http -s user npiwho https://npiwho.com/mcp

-s user makes it available in every project; leave it out to add it to the current project only. Check with claude mcp list, which should show npiwho as connected, then open a new session and ask a question. To remove it: claude mcp remove -s user npiwho.

Claude.ai (web and desktop app). Settings → Connectors → Add custom connector. Name it NPI Who, paste the URL, leave authentication empty, save. In a chat, open the tools menu and turn the connector on.

ChatGPT. Settings → Connectors → Create (developer mode has to be on). Paste the URL, choose No authentication, save. Then enable it for a chat from the tools menu.

Codex (terminal):

codex mcp add npiwho --url https://npiwho.com/mcp

Cursor, Windsurf, VS Code and other clients that read a JSON config. Add this to the client’s MCP settings file (in Cursor: Settings → MCP → Add new server):

{
  "mcpServers": {
    "npiwho": { "type": "http", "url": "https://npiwho.com/mcp" }
  }
}

Once connected, ask in plain language: “What do the public records say about NPI 1366487498?”, “Who is at (210) 489-7220?”, “Which hospices in Austin, Texas are non-profit?” The assistant picks the tool; you do not call it yourself.

Tools

Tool	Returns
lookup_provider	One NPI: the registry record, and what the public files have on the provider (Open Payments total, Medicare billing, OIG exclusion, Medicare clinician record, facility enrollments, claimed-page details), each pointing to the page section with the detail.
search_providers	Individuals or organizations by name, optionally within a state. Up to 20, best match first.
lookup_phone	Who lists a given phone number, in any US format. Numbers a provider asked to withhold are not returned.
nearby_providers	The nearest providers of the same specialty, from an NPI or from a ZIP code and taxonomy code.
list_facilities	Medicare-certified home health agencies, hospices, hospitals, nursing homes, or HRSA health centers in a state or city.
data_sources	Which files the answers come from and their snapshot dates.

The answer will carry links to the pages here.

What the data is

Public federal records joined on the NPI: the NPPES registry, CMS Open Payments, Medicare Part B and Part D, the OIG exclusion list, CMS Doctors and Clinicians, Medicare facility enrollments, and HRSA’s health center list. The files and their dates are on the methodology page and in the data_sources tool. None of it is a licence, credential or quality check. Providers can ask for their contact details to be withheld, and those requests apply to the MCP tools exactly as to the pages.

Allowance

About 1,000 tool calls per day per client address, resetting at 00:00 UTC, which covers personal and development use. Calls made through Claude.ai or ChatGPT come from the platform’s addresses and share a larger pool. For more, or for bulk work, write to [email protected]; the per-provider payment totals are also an open dataset.

Run by Derek Hong, Singapore, who also runs this site; see About.