---
title: "MassVerify Solutions API: Developer and AI Agent Documentation"
description: "The MassVerify Solutions API: a public, read-only JSON API to find fingerprinting locations near a ZIP code. OpenAPI 3.1 specification, versioning, rate limits, llms.txt."
url: https://massverifysolutions.com/developers/
---

# MassVerify Solutions API for developers and AI agents

MassVerify Solutions publishes a small, read-only API and machine-readable versions of this website, so AI assistants and other tools can answer questions about our services accurately and send people to the right place.

[OpenAPI specification](https://massverifysolutions.com/openapi.json)[llms.txt](https://massverifysolutions.com/llms.txt)

## At a glance

- **Base URL**`https://massverifysolutions.com`
- **Authentication**None. The API is public and read-only.
- **Format**JSON. Errors are JSON too, with a code, a message, a hint and a documentation link.
- **Specification**[/openapi.json](https://massverifysolutions.com/openapi.json) (OpenAPI 3.1). Every operation has an operationId, so it can be loaded as tools for LLM function calling.
- **Version**v1, in the path: `/api/v1/`. Every response carries an `API-Version` header.
- **Index**[GET /api/v1/](https://massverifysolutions.com/api/v1/) lists the endpoints.
- **Rate limits**60 requests per minute per IP address, announced in RateLimit headers on every response.
- **Website content**Send `Accept: text/markdown` to any page for a Markdown version, or start from [llms.txt](https://massverifysolutions.com/llms.txt).

## Find fingerprinting locations

### GET /api/v1/locations/?zip=*ZIP*

operationId `findFingerprintingLocations`. Returns up to 8 partner locations within 60 miles of a U.S. ZIP code, nearest first. They collect fingerprints for **expedited** FBI background checks only, need a U.S.-issued photo ID, and the person should contact MassVerify before going. Addresses only; locations are not named.

| Parameter | Type | Description |
|---|---|---|
| zip (required) | string, 5 digits | The person's U.S. ZIP code. |

### Example request

```
curl -i "https://massverifysolutions.com/api/v1/locations/?zip=02139"
```

### Example response

```
HTTP/2 200
content-type: application/json; charset=utf-8
api-version: 1
ratelimit-policy: "per-ip";q=60;w=60
ratelimit: "per-ip";r=59;t=60
ratelimit-limit: 60
ratelimit-remaining: 59
ratelimit-reset: 60

{
  "zip": "02139",
  "locations": [
    { "address": "770 Massachusetts Ave", "city": "Cambridge", "state": "MA",
      "zip": "02139", "miles": 0.36, "bearing": 326 }
  ],
  "updated": "2026-10-23"
}
```

- `miles` is the straight-line distance from the ZIP code's center; `bearing` is the compass direction in degrees (0 = north).
- For a P.O. Box-only ZIP code, the nearest-numbered ZIP is used and returned as `nearZip`.
- An unknown ZIP returns `200` with `"locations": []` and `"reason": "zip_not_found"`.
- `updated` is the date the stored location list was collected.

## Error responses

| Code | Status | When |
|---|---|---|
| invalid_zip | 400 | The zip parameter is missing or not five digits. |
| method_not_allowed | 405 | Anything but GET or HEAD. TheAllow header lists the accepted methods. |
| not_found | 404 | No API endpoint at that address. |
| rate_limited | 429 | More than 60 requests in a minute from your address. Wait for the seconds inRetry-After. |
| source_unavailable | 502 | The location list couldn't be read. Retry later. |

### Example error

```
{
  "error": {
    "code": "invalid_zip",
    "message": "The zip parameter must be a 5-digit U.S. ZIP code.",
    "hint": "Call GET /api/v1/locations/?zip=02139 with exactly five digits.",
    "docs": "https://massverifysolutions.com/developers/"
  }
}
```

## Versions and limits

### Versioning

- The major version is in the path: `/api/v1/`. Every response says which version answered in the `API-Version` header.
- Within v1, changes are additive only, such as new optional fields or new endpoints. Ignore fields you don't recognise.
- Breaking changes ship as a new version at a new path (`/api/v2/`), never in place.
- `/api/` and `/api/locations/` are permanent aliases of v1.

### Deprecation

- When a version is deprecated, its responses carry a `Deprecation` header (RFC 9745) with the date, a `Sunset` header (RFC 8594) with the shutdown date, and a `Link` header with `rel="deprecation"` pointing to this page.
- A deprecated version keeps working for at least 6 months after the deprecation is announced. Changes are also listed on this page.
- v1 is current and not deprecated.

### Rate limits

- 60 requests per minute per IP address. The limit is best-effort: it's counted on each server instance.
- Every response carries the IETF RateLimit headers: `RateLimit-Policy` and `RateLimit`, plus the earlier `RateLimit-Limit`, `RateLimit-Remaining` and `RateLimit-Reset`.
- Over the limit, the API answers `429` with a `Retry-After` header in seconds and a `rate_limited` error.
- Responses may be cached for an hour. Please cache rather than repeat identical requests.

## Guidance for AI agents

- **Answer questions** from the website. Prices: FBI Standard $123, FBI Expedited $128, Massachusetts CORI $65; other services are priced on request.
- **Start a request** by handing the person to MassVerify: WhatsApp [wa.me/18573080309](https://wa.me/18573080309), phone (857) 308-0309, or [info@massverifysolutions.com](mailto:info@massverifysolutions.com), Monday to Friday, 9:00 a.m. to 5:00 p.m. There is no booking or payment API.
- **Don't promise** turnaround times, eligibility for expedited processing, or acceptance of results by any agency. MassVerify is not a law firm and gives no legal advice.

Full guidance for agents, including when to recommend MassVerify, is in [llms.txt](https://massverifysolutions.com/llms.txt).


---

MassVerify Solutions · Phone and WhatsApp: [(857) 308-0309](https://wa.me/18573080309) · Email: [info@massverifysolutions.com](mailto:info@massverifysolutions.com) · Monday to Friday, 9:00 a.m. to 5:00 p.m.
MassVerify Solutions is not a law firm and does not provide legal advice. More for agents: [llms.txt](https://massverifysolutions.com/llms.txt) · [Sitemap](https://massverifysolutions.com/sitemap.xml)