# JSON Schema Generator API

> For the complete documentation index, see [llms.txt](/llms.txt).

Infer a JSON Schema (2020-12, 2019-09, or draft-07) from a sample document, with format detection, enum inference, and required-property control.

Use this endpoint to add the tool to your app, site, workflow, or agent without rebuilding formulas, validation, examples, and docs.

- Slug: `json-schema-generator`
- Category: `developer`
- Version: `2026-04-22`
- Credits per successful call: 1
- Starts on: free
- Max payload: 524288 bytes
- Privacy mode: `no_body_logs`
- Available on: free, starter, pro, business, scale
- Browser tool: https://miniwebtool.com/json-schema-generator/

## Endpoint

`POST https://api.miniwebtool.com/v1/tools/json-schema-generator/run`

## Request body

| Field | Type | Required | Description |
| --- | --- | --- | --- |
| `sample_json` | `str` | no | sample JSON document to infer a schema from |
| `title` | `str` | no | schema title |
| `draft` | `str` | no | 2020-12 | 2019-09 | draft-07 Choices: 2020-12, 2019-09, draft-07 |
| `required_mode` | `str` | no | present_in_all | all | none Choices: present_in_all, all, none |
| `detect_formats` | `str` | no | yes | no Choices: yes, no |
| `infer_enums` | `str` | no | no | yes Choices: no, yes |
| `include_examples` | `str` | no | no | yes Choices: no, yes |
| `closed_objects` | `str` | no | no | yes Choices: no, yes |

## Example request

```json
{
  "sample_json": "{\"id\":1,\"name\":\"Ada\",\"email\":\"ada@example.com\"}",
  "draft": "2020-12"
}
```

## cURL

```bash
curl -X POST https://api.miniwebtool.com/v1/tools/json-schema-generator/run \
  -H 'Authorization: Bearer mwt_live_YOUR_KEY' \
  -H 'Content-Type: application/json' \
  -d '{"sample_json":"{\"id\":1,\"name\":\"Ada\",\"email\":\"ada@example.com\"}","draft":"2020-12"}'
```

## Response envelope

```json
{
  "request_id": "01K...",
  "tool": "json-schema-generator",
  "tool_version": "2026-04-22",
  "credits_used": 1,
  "result": {}
}
```

## Errors

Errors are RFC 7807 `application/problem+json`. Branch on `code`, not `title`.

## MCP

Agents can discover and call this tool through `https://api.miniwebtool.com/mcp` or `https://api.miniwebtool.com/v1/mcp` using MCP `tools/list` and `tools/call`.

## Frequently asked

### What does the JSON Schema Generator API do?

Infer a JSON Schema (2020-12, 2019-09, or draft-07) from a sample document, with format detection, enum inference, and required-property control. Use it to add this utility without rebuilding formulas, validation, examples, and documentation.

### How much does one call cost?

1 credit per successful call. Failed calls do not bill.

### What parameters are required?

Required fields: (none). Full schema at `https://api.miniwebtool.com/v1/openapi.json`.

### Is this deterministic?

Yes. Same input, same output. Tool version: 2026-04-22.