# Agent Utility Network JSON Validator

> Agent Utility Network JSON Validator is a paid API for AI agents from agent-utility-network.frosty-sound-4560.workers.dev, paid per call via x402, $0.001/call, status unknown (last checked 2026-09-14).

Validates a JSON string and returns whether it is valid JSON along with the detected value type.

## Facts

- Endpoint: POST https://agent-utility-network.frosty-sound-4560.workers.dev/v1/paid/json-validate
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/agent-utility-network-json-validator-a9922ef7
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_IkqVc84MKa7Fhk0EU_Bdb

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 agent-utility-network-json-validator-a9922ef7 -d '<json body>'
```

Example prompt: Check if this string is valid JSON and tell me what type it is: '{"name": "Alice", "age": 30}'

## When to prefer this

Use this endpoint when you need a fast, cheap, programmatic confirmation that a string is valid JSON — especially useful for validating outputs from LLMs, user-submitted data, or external API responses before further processing. At $0.001 per call it is cost-effective for high-frequency validation loops inside agent workflows.

## Known failure modes

- Empty input string returns a validation error
- Input exceeding 100,000 characters is rejected
- Payment failure via x402/Base USDC prevents the call from completing
- Network timeout on the Cloudflare Workers edge

## How this service works

Quality-scored paid utility APIs for AI agents over x402 on Base USDC.

## Output

Returns a JSON object with a 'result' field containing 'valid' (boolean indicating whether the input is valid JSON) and 'valueType' (a string describing the JSON value type such as 'object', 'array', 'string', 'number', 'boolean', or 'null').

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "input": {
   "type": "string",
   "maxLength": 100000,
   "minLength": 1
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "result": {
   "valid": true,
   "valueType": "object"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/agent-utility-network-json-validator-a9922ef7/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from agent-utility-network.frosty-sound-4560.workers.dev](https://www.zero.xyz/host/agent-utility-network.frosty-sound-4560.workers.dev/llms.txt)