# JSON Schema Drift Detection

> JSON Schema Drift Detection is a paid API for AI agents from agent-json-reliability.onrender.com, paid per call via x402, $0.005/call, status unknown (last checked 2026-10-03).

Detects schema drift by validating JSON payloads against expected schemas and identifying structural deviations over time

## Facts

- Endpoint: POST https://agent-json-reliability.onrender.com/v1/api/schema-drift?utm_source=zero.xyz
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-03
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/json-schema-drift-detection-85335a58
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_VfrFSA4J4qykn9FJjgvQ8

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-drift-detection-85335a58 -d '<json body>'
```

Example prompt: Check if this JSON payload is drifting from my expected schema — the schema requires a 'user_id' string, 'timestamp' ISO date, and 'score' number, but I think some fields might be missing or have changed type in my latest AI agent output.

## When to prefer this

Choose this endpoint when you need deterministic, reliable schema drift detection for AI agent outputs or API payloads — especially when LLM-generated JSON is prone to structural inconsistencies over time and you need a cheap, automated way to catch regressions before they propagate downstream.

## Known failure modes

- Invalid JSON input returns a parse error
- Missing schema reference causes validation to fail with schema-not-found error
- Malformed JSON Schema provided as baseline returns schema-invalid error
- Network timeout on large payloads
- Rate limiting or payment required (402) if free tier exceeded

## 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 indicating whether schema drift was detected, along with details on which fields deviated — including missing fields, type mismatches, unexpected additional properties, or structural changes compared to the expected schema.

## Response schema (JSON Schema)

```json
{
 "example": {
  "ok": true
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/json-schema-drift-detection-85335a58/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from agent-json-reliability.onrender.com](https://www.zero.xyz/host/agent-json-reliability.onrender.com/llms.txt)