# User-Agent Bot Detection

> User-Agent Bot Detection 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).

Detects whether a given User-Agent header string belongs to a bot or automated client

## Facts

- Endpoint: POST https://useragent.openverbs.com/v1/is-bot
- 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-bot-detection-04a5467d
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_FNIqtKbPUIqrWc1NNeHqt

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-bot-detection-04a5467d -d '<json body>'
```

Example prompt: Can you check if this user agent string is a bot: 'Mozilla/5.0 (compatible; Googlebot/2.1; +http://www.google.com/bot.html)'?

## When to prefer this

Choose this endpoint when you need a quick, lightweight check on whether a specific User-Agent string belongs to a bot or automated client — ideal for real-time request filtering, analytics deduplication, or access control logic where you only have the User-Agent header available and need an instant verdict without full behavioral analysis.

## Known failure modes

- Missing or empty 'ua' field returns validation error
- Unknown or ambiguous user agent strings may result in uncertain classification
- Very new or custom bot user agents may not be recognized
- Malformed JSON body returns 400-level error
- Rate limiting or payment failure returns 402/429 errors

## How this service works

Detect whether a User-Agent belongs to a known bot, crawler, AI agent or HTTP tool, and if so return its name and category (search, social, seo, ai, monitoring, tool, …).

## Output

A classification result indicating whether the provided User-Agent string is identified as a bot, likely including a boolean is-bot flag and potentially a confidence score or bot type classification.

## Request schema (JSON Schema)

```json
{
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "type": "object",
 "properties": {
  "input": {
   "type": "object",
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "type": "string",
     "enum": [
      "POST"
     ]
    },
    "bodyType": {
     "type": "string",
     "enum": [
      "json",
      "form-data",
      "text"
     ]
    },
    "body": {
     "type": "object",
     "properties": {
      "ua": {
       "type": "string",
       "description": "The User-Agent header string."
      }
     },
     "required": [
      "ua"
     ],
     "additionalProperties": false
    }
   },
   "required": [
    "type",
    "method",
    "bodyType",
    "body"
   ],
   "additionalProperties": false
  }
 },
 "required": [
  "input"
 ]
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/user-agent-bot-detection-04a5467d/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)