# Json Flatten — REST API endpoint `json-flatten`

Flatten a nested JSON object into a single-level map with dot-separated keys.

- Category: data
- MCP server: https://mcp.findutils.com/ (Streamable HTTP, no API keys, 120 req/min per IP)
- REST endpoint: POST https://api.findutils.com/api/tools/json-flatten/execute (no API keys, 60 req/min per IP)
- Reference page: https://findutils.com/api/json-flatten/
- Same tool on the other surface: https://findutils.com/mcp/json-flatten/

## Call the endpoint (verified example)

```bash
curl -X POST https://api.findutils.com/api/tools/json-flatten/execute \
  -H "Content-Type: application/json" \
  -d '{
    "json": "{\"a\":{\"b\":1}}"
  }'

# Parameter schema
curl https://api.findutils.com/api/tools/json-flatten
```

## Input schema

| Argument | Type | Required | Description |
|---|---|---|---|
| `json` | string | yes | JSON object to flatten. |
| `separator` | string | no | Key separator. Defaults to ".". Default: `"."`. |

Example arguments (verified):

```json
{
  "json": "{\"a\":{\"b\":1}}"
}
```

Decoded `json` argument (readability only — send it as a string):

```json
{
  "a": {
    "b": 1
  }
}
```

OpenAPI 3.1 spec: https://findutils.com/api/openapi.json · Interactive docs: https://findutils.com/api/docs/

## Also an MCP tool

```bash
claude mcp add findutils --transport http https://mcp.findutils.com/
```

Then ask the client to call `findutils:json_flatten`. Full MCP reference: https://findutils.com/mcp/json-flatten/

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