# Mat Web & Data Toolkit – JSON Validator

> Mat Web & Data Toolkit – JSON Validator is a paid API for AI agents from automatom.matt-d59.workers.dev, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-18).

Validates a JSON string and returns structural metadata including key count, depth, byte size, validity flag, and pretty-printed output.

## Facts

- Endpoint: GET https://automatom.matt-d59.workers.dev/jsonvalidate?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-18
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/mat-web-data-toolkit-json-validator-8a9e2092
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_E3F-tdIZyc3xc87U8FO5d

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 mat-web-data-toolkit-json-validator-8a9e2092
```

Example prompt: Can you validate this JSON for me and tell me if it's valid, how many keys it has, and show me a pretty-printed version: '{"name":"Alice","age":30}'?

## When to prefer this

Choose this endpoint when you need a lightweight, fast JSON validation and introspection tool — especially useful for checking payload validity before sending to downstream APIs, debugging malformed JSON, or understanding the structure of an unknown JSON blob without needing a full schema validator.

## Known failure modes

- Invalid or missing `json` query parameter returns an error response
- Extremely large JSON payloads may exceed worker memory or timeout limits
- Non-JSON strings will return valid=false with limited structural metadata
- Network errors or Cloudflare worker failures may return a 5xx status

## How this service works

Fetches a public web page and returns its title, meta description, outbound links and readable plain text as JSON.

## Output

Returns a JSON object with: `valid` (boolean indicating JSON validity), `keys` (number of top-level keys), `depth` (nesting depth), `bytes` (byte size of the input), `type` (data type of the root element), and `pretty` (a pretty-printed string version of the parsed JSON).

## 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": [
      "json"
     ],
     "properties": {
      "json": {
       "type": "string"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "keys": 2,
  "type": "object",
  "bytes": 17,
  "depth": 2,
  "valid": true,
  "pretty": "{\n  \"a\": 1,\n  \"b\": [\n    1,\n    2\n  ]\n}"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/mat-web-data-toolkit-json-validator-8a9e2092/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from automatom.matt-d59.workers.dev](https://www.zero.xyz/host/automatom.matt-d59.workers.dev/llms.txt)