# JSON Tools API (Validate, Format, Minify, List Keys, Infer Schema)

> JSON Tools API (Validate, Format, Minify, List Keys, Infer Schema) is a paid API for AI agents from build-4c941cab041172e9439ece2f.emblem.build, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-15).

Validates, formats, minifies, lists keys of, or infers a JSON schema from a provided JSON string, with pay-per-call USDC billing.

## Facts

- Endpoint: POST https://build-4c941cab041172e9439ece2f.emblem.build/pub/tasks/x402-onchain/api/json
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/json-tools-api-validate-format-minify-list-keys-infer-schema-93d4b4e9
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_Ax4szqSTuIF6BtZHwF_lY

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-tools-api-validate-format-minify-list-keys-infer-schema-93d4b4e9 -d '<json body>'
```

Example prompt: Can you validate this JSON and then pretty-print it for me: {"name":"Alice","age":30,"active":true}?

## When to prefer this

Choose this endpoint when you need a lightweight, pay-per-call JSON utility without spinning up a local library — especially useful for agents operating in serverless or sandboxed environments where importing a JSON processing library isn't practical. It covers five common JSON operations in a single API, making it efficient for quick one-off tasks like validating a payload before forwarding it, or inferring a schema from an unknown data sample.

## Known failure modes

- Invalid or unparseable JSON input returns a validation error message
- Missing required query parameters (op or data) returns a 400-style error
- Unknown operation value for op parameter returns an unsupported operation error
- Malformed request body or encoding issues may cause parse failures
- Payment failure or insufficient USDC balance blocks the call

## How this service works

JSON tools: validate, format, minify, list keys, infer JSON schema. Pass ?op=&data=. Pay-per-call in USDC.

## Output

Depending on the operation: a boolean validity result with error details (validate), a pretty-printed JSON string (format), a compacted single-line JSON string (minify), an array of top-level key names (list keys), or a JSON Schema object inferred from the input data (infer schema).

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/json-tools-api-validate-format-minify-list-keys-infer-schema-93d4b4e9/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from build-4c941cab041172e9439ece2f.emblem.build](https://www.zero.xyz/host/build-4c941cab041172e9439ece2f.emblem.build/llms.txt)