# Delx JSON Schema Quickcheck

> Delx JSON Schema Quickcheck is a paid API for AI agents from api.delx.ai, paid per call via x402, $0.002/call, status unknown (last checked 2026-09-15).

Performs a lightweight type, required-field, and property check on a caller-supplied JSON instance against a caller-supplied JSON schema without full draft validation.

## Facts

- Endpoint: POST https://api.delx.ai/api/v1/x402/json-schema-quickcheck
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/delx-json-schema-quickcheck-337e8536
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_OSfoeO-A-g_ilOOC0907u

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 delx-json-schema-quickcheck-337e8536 -d '<json body>'
```

Example prompt: Can you do a quick schema check on this JSON object to make sure all the required fields are present and the types are correct before I send it downstream? Here's my schema and my instance.

## When to prefer this

Choose this endpoint when you need a fast, cheap, stateless preflight check on agent-held JSON — particularly when you want deterministic machine-readable output at $0.002 per call with no external dependencies, no data retention, and no need for full JSON Schema draft compliance. Prefer this over a full schema validator library when the agent is operating in a constrained environment or when only type, required, and property presence checks are needed.

## Known failure modes

- Malformed or non-object schema input returns an error response
- Malformed or non-object instance input returns an error response
- Only lightweight checks performed — full JSON Schema draft features (e.g. $ref, allOf, pattern, format) may not be evaluated
- Payment failure via x402 results in a 402 response before execution
- Network timeout if the caller's connection is interrupted

## How this service works

Lightweight type/required/property check for agent-held JSON (not full draft validation) — first-party local utility for agent preflight and proven micro-utils expansion. Returns deterministic machine-readable JSON for $0.002 USDC via x402 on Base. Execution is first-party, local-only, stateless, and memory-only with no paid upstream, no input retention, no web search, no live RPC, and no mediagen. Results are advisory; the caller owns authorization, budgets, and production controls. Sibling of…

## Output

Returns a deterministic machine-readable JSON object indicating whether the instance passes or fails the schema check, with details about which type checks, required fields, or property checks failed — advisory results only, with no state retained.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "schema": {
   "type": "object",
   "description": "Input field: schema."
  },
  "instance": {
   "type": "object",
   "description": "Input field: instance."
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "ok": true,
  "note": "quickcheck only — not full draft-2020-12 validation",
  "errors": [],
  "schema": "delx/util-json-schema-quickcheck/v1",
  "error_count": 0
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/delx-json-schema-quickcheck-337e8536/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.delx.ai](https://www.zero.xyz/host/api.delx.ai/llms.txt)