# JSON Schema Validator

> JSON Schema Validator is a paid API for AI agents from jsonschema.openverbs.com, paid per call via x402, $0.004/call, status unknown (last checked 2026-09-14).

Validates any JSON value against a provided JSON Schema (Draft 2020-12) and returns whether the data conforms

## Facts

- Endpoint: POST https://jsonschema.openverbs.com/v1/validate
- Price: $0.004/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/json-schema-validator-8df3fe6e
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_I18sGUGX76ZNoXt1DX_2P

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 json-schema-validator-8df3fe6e -d '<json body>'
```

Example prompt: Can you validate this JSON object against my schema to check if it's valid? The schema requires a 'name' string and an 'age' integer, and I want to test the object {"name": "Alice", "age": 30}.

## When to prefer this

Use this endpoint when you need a quick, paid, API-accessible JSON Schema validation without running your own validation library — especially in agent workflows where you need programmatic schema conformance checks as a step, or when validating untrusted external data against a known schema before further processing.

## Known failure modes

- Invalid JSON Schema provided — schema object is malformed or uses unsupported keywords
- Missing required fields in request body (schema or data fields absent)
- Internal validation engine error for extremely complex or recursive schemas
- Network timeout for unusually large JSON payloads

## How this service works

Validate a JSON value against a JSON Schema (draft-07, with the standard string formats enabled). An invalid schema is rejected as a clean 400 before payment; a valid schema that the data simply fails to satisfy is a successful result with valid=false and a list of errors (path, keyword, message).

## Output

Returns a validation result indicating whether the provided JSON data conforms to the given JSON Schema, along with any validation errors, failed constraints, or path-specific issues found during schema evaluation.

## 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": [
      "schema",
      "data"
     ],
     "properties": {
      "data": {
       "description": "The value to validate (any JSON type)."
      },
      "schema": {
       "type": "object",
       "description": "The JSON Schema to validate against."
      }
     },
     "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/json-schema-validator-8df3fe6e/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from jsonschema.openverbs.com](https://www.zero.xyz/host/jsonschema.openverbs.com/llms.txt)