# SiteCheck NPI Registry Lookup

> SiteCheck NPI Registry Lookup is a paid API for AI agents from api.sitecheck-api.workers.dev, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-19).

Looks up US healthcare providers by NPI number, name, or state using the NPPES NPI Registry

## Facts

- Endpoint: GET https://api.sitecheck-api.workers.dev/api/npi?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-19
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/sitecheck-npi-registry-lookup-cbb3ff8b
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_a0OYARoZs9IB5wyJkQ1dd

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability sitecheck-npi-registry-lookup-cbb3ff8b
```

Example prompt: Can you look up NPI number 1063837144 and tell me that provider's name, specialty, and practice address?

## When to prefer this

Use this endpoint when you need to look up or verify US healthcare provider information from the official NPPES NPI Registry, including active status, specialty taxonomy, credentials, and practice location. Ideal for billing validation, provider enrichment, referral workflows, or compliance checks where authoritative government data is required. Prefer this over general web searches when you need structured, reliable NPI data with attribution.

## Known failure modes

- No provider found matching the given NPI, name, or state — returns empty providers array
- Invalid NPI format (must be 10-digit number) — may return validation error or empty result
- Ambiguous name search returns many results or too many to return cleanly
- NPPES upstream API unavailability causing timeout or error
- State code not recognized if not two-letter uppercase format

## How this service works

US healthcare providers from the NPPES NPI Registry: look up one by its 10-digit NPI (check digit verified) or search by name with an optional state. Each provider gives type, name, credential, status, primary taxonomy and practice address. Information only, not medical advice.

## Output

Returns a JSON object with the matched provider's NPI, full name, provider type (individual or organization), active status, practice address (street, city, state, postal code), phone number, taxonomy/specialty, and credential, along with the query parameters used and a timestamp. Attribution to the NPPES NPI Registry is included.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [],
     "properties": {
      "name": {
       "type": "string",
       "description": "First and last name, or last name"
      },
      "state": {
       "type": "string",
       "description": "Two-letter US state, e.g. CA"
      },
      "number": {
       "type": "string",
       "description": "10-digit NPI"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "query": {
   "name": null,
   "state": null,
   "number": "1063837144"
  },
  "source": "https://npiregistry.cms.hhs.gov/api/ (NPPES NPI Registry v2.1)",
  "checkedAt": "2026-10-14T07:00:43.329Z",
  "providers": [
   {
    "npi": "1063837144",
    "name": "JACKELYN RAE KELLEY",
    "type": "individual",
    "status": "active",
    "practice": {
     "city": "SAN FRANCISCO",
     "phone": "724-544-3437",
     "state": "CA",
     "address": "1001 POTRERO AVE WARD 93",
     "postalCode": "941103518"
    },
    "taxonomy": "Social Worker, Clinical",
    "credential": "LCSW"
   }
  ],
  "attribution": "NPPES NPI Registry (US government data)"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/sitecheck-npi-registry-lookup-cbb3ff8b/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.sitecheck-api.workers.dev](https://www.zero.xyz/host/api.sitecheck-api.workers.dev/llms.txt)