# AgentShelf JSON Schema Validator

> AgentShelf JSON Schema Validator is a paid API for AI agents from agentshelf.syntexa.ch, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-01).

Validates a JSON value against a provided JSON Schema and returns whether it conforms, with no network or LLM calls involved.

## Facts

- Endpoint: POST https://agentshelf.syntexa.ch/v1/json-schema-check?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-01
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/agentshelf-json-schema-validator-76db4a5a
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_uU3ga_4Kvy53cky-9T6bO

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 agentshelf-json-schema-validator-76db4a5a -d '<json body>'
```

Example prompt: Can you check if this JSON object {"name": "Alice", "age": 30} is valid according to the schema {"type": "object", "properties": {"name": {"type": "string"}, "age": {"type": "integer"}}, "required": ["name", "age"]}?

## When to prefer this

Choose this endpoint when you need a fast, deterministic, offline JSON Schema validation with no LLM involvement and no external network calls. It is ideal for agents that need to validate structured data conformance within a pipeline at low cost ($0.001 USDC). Prefer the free sandbox endpoint POST /v1/sandbox/json-schema-check first if available; use this paid endpoint when the sandbox is unavailable or rate-limited.

## Known failure modes

- Malformed JSON data causes a parse error response
- Invalid or malformed JSON Schema object results in a schema parse error
- Missing required fields (data or schema) returns a 400 bad request
- Network or service unavailability returns a 5xx error
- Unsupported JSON Schema draft or keywords may result in partial or failed validation

## How this service works

Call when an agent needs a JSON value checked against a JSON Schema. No network. Exact $0.001 USDC. Prefer unpaid POST /v1/sandbox/json-schema-check first.

## Output

Returns a conformance result indicating whether the provided JSON data value is valid against the given JSON Schema, along with any validation errors or constraint violations if the data does not conform.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "data": {
   "examples": [
    {
     "name": "Ada"
    }
   ],
   "description": "JSON value to validate."
  },
  "schema": {
   "type": "object",
   "examples": [
    {
     "type": "object",
     "required": [
      "name"
     ],
     "properties": {
      "name": {
       "type": "string"
      }
     }
    }
   ],
   "description": "JSON Schema object. Example: {type:object, required:[name]}.",
   "additionalProperties": {}
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/agentshelf-json-schema-validator-76db4a5a/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from agentshelf.syntexa.ch](https://www.zero.xyz/host/agentshelf.syntexa.ch/llms.txt)