NPI Registry

Name: NPI Registry MCP Server
Availability: InStock
Author: NPI Registry

Healthcare3 toolsNo Auth Required

Validate, look up and search US healthcare provider records from the CMS NPPES NPI Registry inside your AI agent. 3 read-only tools, no sign-in, built and operated by Anthropic — public provider practice information, never patient data.

Verified connector

Listed by Anthropic as an Anthropic-built connector in its Connectors Directory.

Connection checked by Agentman on 18 August 2026.

Anthropic states this reflects the level of review a connector received, not a security audit.

Connect NPI Registry via MCP

https://hcls.mcp.claude.com/npi_registry/mcp

Works in any MCP-compatible client. In Agentman Studio it is one click — no config file to edit.

NPI Registry Tools & Capabilities (3)

npi_validateRead-only

Validate NPI format and Luhn check digit. Instant local validation - no API call. WHEN TO USE: - ALWAYS use before npi_lookup to catch typos and save API calls - Validating NPI numbers from external sources (documents, forms, databases) - Quick format check without network dependency - Pre-filtering lists of NPIs before bulk lookups WHAT THIS CHECKS: 1. Format: Exactly 10 digits, numeric characters only (0-9) 2. Check digit: Valid Luhn algorithm calculation with healthcare prefix (80840) WHAT THIS DOES NOT CHECK: - Whether the NPI is actually assigned to a provider in NPPES - Whether the provider is active or deactivated - Whether the provider is licensed or credentialed - Whether the NPI has ever been issued VALIDATION RESULTS: ✓ VALID: NPI has correct format AND valid check digit -> Proceed to npi_lookup to verify assignment ✗ INVALID FORMAT: Not 10 digits or contains non-numeric characters -> Cannot be a real NPI, check for typos ✗ INVALID CHECK DIGIT: 10 digits but check digit doesn't match -> Likely a typo in one of the digits IMPORTANT: A valid check digit does NOT guarantee the NPI exists! Many mathematically valid NPIs have never been assigned. Use npi_lookup after validation to confirm the NPI is in NPPES. EXAMPLES: - '1234567893' -> VALID (correct format + valid check digit) - '123456789' -> INVALID (only 9 digits) - '1234567890' -> INVALID (wrong check digit, expected 3) - '123456789X' -> INVALID (contains non-digit character) - ' 1234567893 ' -> VALID (whitespace is stripped automatically)

npi_lookupRead-only

Get comprehensive provider details by NPI number from the CMS NPPES Registry. WHEN TO USE: - You have a specific NPI and need full provider information - Verifying provider credentials, specialty, or practice location - Following up on results from npi_search to get complete details - Cross-referencing clinical trial investigators with US credentials - Getting raw API response for advanced data extraction USE npi_search INSTEAD FOR: - Finding providers by name, location, or specialty - When you don't have a specific NPI number - Browsing providers in a geographic area WHAT THIS RETURNS: Basic Information: - Provider type: Individual (NPI-1) or Organization (NPI-2) - Name: Full name (individuals) or Legal Business Name (organizations) - Credentials: MD, DO, RN, PA-C, NP, etc. (for individuals) - Status: 'A' (Active) or 'D' (Deactivated) - Enumeration date: When the NPI was first assigned - Last updated: When the record was last modified Specialty/Taxonomy: - Primary taxonomy code: NUCC healthcare provider taxonomy code - Primary taxonomy description: Human-readable specialty name - License state and number: From primary taxonomy Location: - Practice address: Primary practice location with full address - Phone number: Practice telephone (if available) Advanced: - Raw API response: Complete NPPES data including: - All taxonomies (up to 15) - Other identifiers (state license, DEA, etc.) - Other practice locations - Authorized officials (for organizations) - Endpoints (health information exchange) NOTE: Automatically validates NPI format before API call. Returns found=false if NPI is valid but not assigned to any provider. IMPORTANT CAVEATS: - Having an NPI does NOT guarantee the provider is currently licensed - Provider self-reports data; NPPES does not verify accuracy - Deactivated providers remain in database but should not be used for billing - Verify credentials through state licensing boards for official confirmation

npi_searchRead-only

Search the CMS NPPES Registry for healthcare providers by name, location, specialty, or organization. WHEN TO USE: - Finding providers by name (e.g., 'Find Dr. John Smith') - Finding providers by specialty (e.g., 'Cardiologists in Boston') - Finding organizations (e.g., 'Mayo Clinic locations') - Verifying clinical trial investigators have US credentials - Building provider networks by location or specialty - Finding all providers at a specific facility USE npi_lookup INSTEAD FOR: - When you already have a specific NPI number - Getting full details including raw API response SEARCH REQUIREMENTS: - At least one search parameter required (besides enumeration_type/country_code) - State cannot be the only criterion - must combine with name, specialty, or city - Country code alone only works for non-US countries WILDCARD SUPPORT (min 2 characters before *): - first_name: 'Jo*' matches John, Joseph, Jonathan - last_name: 'Smi*' matches Smith, Smithson, Smitty - organization_name: 'Mayo*' matches Mayo Clinic, Mayo Foundation - taxonomy_description: 'Cardio*' matches Cardiology, Cardiovascular Disease - postal_code: '212*' matches all ZIP codes starting with 212 NAME ALIAS FEATURE (DEFAULT: ON): Automatically expands first name searches to include common nicknames: - Robert -> also finds Bob, Rob, Robbie, Bobby - William -> also finds Bill, Will, Billy, Willy - Elizabeth -> also finds Beth, Liz, Betty, Eliza - Michael -> also finds Mike, Mick, Mickey Set use_first_name_alias=false for exact match only. PAGINATION: - Maximum 200 results per request (limit parameter) - Skip up to 1000 records (skip parameter) - Maximum 1,200 total results accessible (6 requests × 200) - Use next_skip from response to get next page - Set limit=200 for comprehensive searches COMMON SPECIALTY SEARCHES (taxonomy_description): - Physicians: 'Internal Medicine', 'Family Practice', 'Cardiology', 'Oncology' - Surgeons: 'Orthopedic Surgery', 'General Surgery', 'Neurosurgery' - Mental Health: 'Psychiatry', 'Psychology', 'Clinical Social Worker' - Allied Health: 'Physical Therapist', 'Nurse Practitioner', 'Physician Assistant' - Organizations: 'General Acute Care Hospital', 'Pharmacy', 'Clinical Laboratory' EXAMPLES: - Find cardiologists in Boston: taxonomy_description='Cardiology', city='Boston', state='MA' - Find Dr. Smith (individual): first_name='John', last_name='Smith', enumeration_type='NPI-1' - Find Mayo Clinic (organization): organization_name='Mayo Clinic', enumeration_type='NPI-2' - Find oncologists in California: taxonomy_description='Oncology', state='CA', limit=100 - Find all pharmacies in NYC: taxonomy_description='Pharmacy', city='New York', state='NY' - Find nurse practitioners in Texas: taxonomy_description='Nurse Practitioner', state='TX' - Exact name match: first_name='Robert', use_first_name_alias=false

Read from the server on 2026-08-18, including each tool's own safety annotations.

Limits

Provider data only — never patient data. No tool takes a patient, member, claim, diagnosis, encounter, plan or date-of-service parameter, and none returns clinical information. Do not paste patient information into a prompt for this connector; there is nowhere for it to go.
It is a named-person index, and it should be used as a routing and verification tool. Search by name is supported, nickname expansion is on by default, and searches can target the mailing address as well as practice locations. Using it to compile profiles of individuals is not what CMS published the registry for, and this connector should not be built into one.
Self-reported, unverified, and stale silently. CMS does not check what providers enter. A provider who never updates NPPES returns a well-formed, confident, out-of-date address and phone number, and last_updated is the only currency signal. Confirm licensure with the relevant state licensing board, which is the connector's own advice.
Deactivation is not reliably reported. The schema documents a D status, but CMS's public registry states it does not display NPIs that are not in service — so a deactivated NPI likely returns not-found, indistinguishable from an NPI that was never assigned. CMS ships a separate monthly deactivation file for this.
A valid check digit proves nothing about a provider. npi_validate confirms format and Luhn arithmetic only. Many mathematically valid NPIs have never been issued, and CMS describes the NPI as an intelligence-free identifier whose digits encode no state, specialty or status.
United States only. The server's own instructions state international providers will not appear.
1,200 results maximum, over six requests. 200 per request and a skip ceiling of 1,000, per CMS. Broad searches are samples, not enumerations, and the total field will exceed what you can page through. CMS's web interface uses a different cap of 2,100.
There is an hourly query limit, and bulk use is out of scope. CMS has rate-limited registry queries per hour since 25 June 2024 and states that bulk queries must use the data-dissemination download file instead. The connector does not mention this anywhere.
npi_search with no arguments returns an empty result rather than an error. We observed this live. An empty result set is not evidence that no matching providers exist.
No network, contract, quality or sanction data. NPPES carries none of it. The connector cannot confirm insurance participation, exclusion-list status, board certification, malpractice history or patient volume.
No writes of any kind. All three tools are annotated read-only, non-destructive and idempotent. The connector cannot create, correct, update or deactivate an NPI record.
Three prompts exist that the directory does not advertise. Two of the three could not be rendered with a placeholder NPI, so their template text is unread and no claim is made about it.
Anthropic calls the healthcare bundle experimental. Its own README states the plugin is provided as-is for evaluation against test or sandbox systems, is not validated for clinical use, is not a medical device, and should not drive patient-care or coverage decisions without qualified human review.
What we did and did not do. Our check was a read-only initialize, tools/list, prompts/list and resources/list handshake, plus two deliberately safe tool calls: npi_validate on 1234567890, the tool's own documented invalid example, which performs no registry query; and npi_search with no arguments, which returned an empty set. No lookup was performed against any real provider's NPI, and no real provider's name, identifier, address or telephone number appears anywhere in this work.

Frequently asked questions

Does the NPI Registry connector return patient data or protected health information?

No. It returns healthcare provider practice information only — the fields CMS publishes about people and organisations who hold a National Provider Identifier. No tool takes a patient, member, claim, diagnosis or date-of-service parameter, and none returns clinical information. There is nowhere in this connector for protected health information to enter or appear.

Whose data is in the NPI Registry, and why is it public?

It is data about healthcare providers, published by the Centers for Medicare and Medicaid Services under federal law at 45 CFR Part 162. CMS states it publishes the parts of an NPI record that have public relevance — name, specialty and practice address — and that only Freedom of Information Act disclosable fields are viewable. The registry exists so payers and providers can route claims correctly.

Can I search the NPI Registry by a person's name alone?

Yes, and that is a deliberate design of the CMS registry rather than something the connector adds. The npi_search tool accepts a first and last name with trailing wildcards after two characters, and expands nicknames by default. Searching by state alone is refused; state must be combined with a name, city or specialty.

Does an NPI in the registry mean the provider is licensed?

No. CMS states plainly on its own data pages that issuance of an NPI does not ensure or validate that the healthcare provider is licensed or credentialed. The connector's own tool description repeats it. NPPES data is self-reported by providers and CMS does not verify accuracy, so confirm licensure through the relevant state licensing board.

Does the NPI Registry connector need a sign-in or an API key?

No. We opened an anonymous handshake on 2026-08-18 and it returned all three tool definitions, then executed one read-only tool call with no credential of any kind and got a normal result. Anthropic's directory records the server as authless with a no_auth posture, and the host publishes no OAuth protected-resource descriptor at any of the three locations we probed.

Will the connector tell me whether a provider is deactivated?

Not reliably. The output schema carries a status field documented as A for active or D for deactivated, but CMS's own public registry states it does not display information about NPIs that are not in service. So a deactivated NPI is more likely to come back as not found than as status D. CMS publishes a separate monthly deactivation file.

Can this connector confirm which insurance networks a provider participates in?

No. NPPES carries no payer-network or contract data at all. The server ships a prompt template named verify_network_participation, and what it can actually support is comparing registry facts — specialty taxonomy, practice state, licence state — against requirements you supply. Network participation itself must come from the payer's own directory or contract records.