# User-Agent Classifier

> User-Agent Classifier is a paid API for AI agents from useragent.openverbs.com, paid per call via x402, $0.002/call, status unknown (last checked 2026-09-14).

Classifies a User-Agent header string to identify the browser, OS, device type, or bot behind an HTTP request

## Facts

- Endpoint: POST https://useragent.openverbs.com/v1/classify
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/user-agent-classifier-09ef8d8b
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_FiPU6to5tGo2A5o7MJokO

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 user-agent-classifier-09ef8d8b -d '<json body>'
```

Example prompt: Can you classify this user-agent string for me and tell me what browser, OS, and device type it represents: 'Mozilla/5.0 (iPhone; CPU iPhone OS 16_0 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/16.0 Mobile/15E148 Safari/604.1'?

## When to prefer this

Use this endpoint when you need real-time, per-request classification of User-Agent strings — ideal for server-side analytics, access control, bot detection, and device-specific routing. Prefer it over regex-based libraries when you want a hosted, maintained classification service that handles edge cases and evolving user agent formats without managing local databases.

## Known failure modes

- Missing or empty 'ua' field returns a validation error
- Malformed or unrecognized user-agent strings may return low-confidence or unknown classifications
- Network errors or service unavailability return non-2xx HTTP responses
- Incorrect bodyType specification may cause request parsing failures

## How this service works

Classify a User-Agent by device form factor and return convenience booleans (isBot, isMobile, isTablet, isDesktop, isTouchCapable) for routing decisions.

## Output

Returns a structured classification of the submitted User-Agent string, including browser name and version, operating system, device type (mobile/desktop/tablet), and whether the agent is a bot or human client.

## 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",
    "bodyType",
    "body"
   ],
   "properties": {
    "body": {
     "type": "object",
     "required": [
      "ua"
     ],
     "properties": {
      "ua": {
       "type": "string",
       "description": "The User-Agent header string."
      }
     },
     "additionalProperties": false
    },
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "POST"
     ],
     "type": "string"
    },
    "bodyType": {
     "enum": [
      "json",
      "form-data",
      "text"
     ],
     "type": "string"
    }
   },
   "additionalProperties": false
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/user-agent-classifier-09ef8d8b/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from useragent.openverbs.com](https://www.zero.xyz/host/useragent.openverbs.com/llms.txt)