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JSON Contract Check
x402
JSON Contract Check is a paid API for AI agents from agent-json-reliability.onrender.com, paid per call via x402, $0.003/call, status unknown (last checked 2026-09-30).
Validates a JSON payload against a contract or schema definition, returning a pass/fail result for AI agent reliability workflows
Price / call$0.003
Success—
StatusUnknown
How this service works
Deterministic JSON repair and JSON Schema validation for AI agents. Free MCP, inspect, validate, repair. Paid POST /v1/json/reliable 0.003 USDC via x402 on Base.
Output
Returns a JSON object with an 'ok' boolean indicating whether the payload passed contract validation, potentially with error details describing schema violations if validation fails.
Example use cases
Agent output schema enforcement
“Before my agent returns its final answer to the user, validate that the JSON it produced matches the required response contract — the output should have a 'result' string field and a 'confidence' number field. Here's the JSON to check: {"result":"approved","confidence":0.92}”
API integration pre-flight check
“I'm about to send a JSON payload to an external API and want to make sure it passes contract validation first. Can you check this against the schema that requires 'orderId' as a string and 'amount' as a positive number? Payload: {"orderId":"ORD-1234","amount":49.99}”
LLM output format validation
“My LLM just generated some JSON but I need to verify it actually follows the contract before using it downstream. Check this output: {"status":"ok","items":[{"id":1,"label":"foo"}]} — it should match a schema with a 'status' string and an 'items' array of objects with 'id' integer and 'label' string.”
Technical details
Endpoint
POSThttps://agent-json-reliability.onrender.com/v1/json/contract-check?utm_source=zero.xyzWhen to prefer
Choose this endpoint when you need deterministic, programmatic JSON contract validation as part of an AI agent pipeline — especially when you want to catch schema violations before passing structured data to downstream services. Prefer it over manual inspection or LLM-based validation when you need reliable, repeatable results with a clear pass/fail signal.
Side effects
- Malformed input JSON causes parsing error and validation cannot proceed
- Schema definition is invalid or missing, returning an error
- Payload structure wildly deviates from contract causing verbose error output
- Service unavailable on Render cold start, resulting in timeout
- Payment not processed correctly via x402, blocking the request
Output
Schema · Response
{
"example": {
"ok": true
}
}Tags
x402
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