# Vextorium JSON Schema Validator

> Vextorium JSON Schema Validator is a paid API for AI agents from api.vextorium.com, paid per call via x402, $0.003/call, status unknown (last checked 2026-10-11).

Validates JSON data against a JSON Schema (drafts 4 through 2020-12) and returns a valid/invalid flag plus detailed error paths and failing rules.

## Facts

- Endpoint: POST https://api.vextorium.com/v1/json-schema-validate?utm_source=zero.xyz
- Price: $0.003/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-11
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/vextorium-json-schema-validator-147a5abf
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_V7ntnhKrF4orjC20TrnNx

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 vextorium-json-schema-validator-147a5abf -d '<json body>'
```

Example prompt: Check this JSON object against my schema and tell me exactly which fields are invalid or missing — I need the path and failing rule for each error: data is {"id": "1", "items": []} and the schema requires id to be an integer and items to have at least one entry.

## When to prefer this

Choose this endpoint when you need precise, path-level validation feedback against a formal JSON Schema (any draft from 4 to 2020-12), especially for verifying LLM-generated structured output or API responses where knowing exactly which fields fail and why is critical. Prefer it over in-process validators when running in a serverless or sandboxed environment without library access, or when you need a neutral third-party validation step in an agentic pipeline.

## Known failure modes

- Invalid or unparseable JSON data returns a parse error rather than schema errors
- Invalid JSON Schema document causes schema compilation failure
- Unsupported schema draft version may result in an error or partial validation
- Network timeout on large deeply-nested documents
- Missing 'data' or 'schema' fields in the request body return a 400-level error

## How this service works

Validate JSON data against a JSON Schema (drafts 4 to 2020-12, with format checks): valid flag and every error with its exact path and failing rule. Check API responses or LLM structured output.

## Output

Returns a JSON object containing the schema draft used, a boolean 'valid' flag, the total number of errors, and a 'detail' array where each entry has the failing rule name (e.g. 'required', 'type'), the exact JSON path to the offending field (e.g. '$.id'), and a human-readable error message.

## 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": {
     "required": [
      "data",
      "schema"
     ],
     "properties": {
      "data": {
       "description": "JSON data"
      },
      "schema": {
       "description": "JSON Schema"
      }
     }
    },
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "POST"
     ],
     "type": "string"
    },
    "bodyType": {
     "enum": [
      "json",
      "form-data",
      "text"
     ],
     "type": "string"
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": [
      "object",
      "null"
     ],
     "properties": {
      "draft": {
       "type": [
        "string",
        "null"
       ]
      },
      "valid": {
       "type": [
        "boolean",
        "null"
       ]
      },
      "detail": {
       "type": [
        "array",
        "null"
       ],
       "items": {
        "type": [
         "null",
         "object"
        ],
        "properties": {
         "rule": {
          "type": [
           "null",
           "string"
          ]
         },
         "route": {
          "type": [
           "null",
           "string"
          ]
         },
         "message": {
          "type": [
           "null",
           "string"
          ]
         }
        }
       }
      },
      "errors": {
       "type": [
        "number",
        "null"
       ]
      }
     }
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "draft": "Draft202012Validator",
  "valid": false,
  "detail": [
   {
    "rule": "required",
    "route": "$",
    "message": "'name' is a required property"
   },
   {
    "rule": "type",
    "route": "$.id",
    "message": "'1' is not of type 'integer'"
   }
  ],
  "errors": 2
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/vextorium-json-schema-validator-147a5abf/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.vextorium.com](https://www.zero.xyz/host/api.vextorium.com/llms.txt)