Data Processing

JSON Unflattener

Convert flattened key-value pairs back to nested JSON objects with support for different key formats and data type inference

json· JSON resultOpen tool

Quick start

Call this tool from your code in three languages.

cURL

curl -X POST 'https://api.elysiatools.com/en/api/tools/json-unflattener' \
  -H 'Content-Type: application/json' \
  -d '{"dataInput":"{\n  \"user.name\": \"John\",\n  \"user.age\": \"30\",\n  \"user.city\": \"New York\",\n  \"settings.theme\": \"dark\",\n  \"settings.notifications\": \"true\"\n}","inputFormat":"json","keyFormat":"nested","delimiter":".","typeInference":"auto","arrayMode":"numeric","mergeStrategy":"override","preserveEmpty":true}'

API reference

Send a POST request with your inputs as JSON. File parameters require a separate upload first.

Endpoint

HTTP

POST https://api.elysiatools.com/en/api/tools/json-unflattener

Parameters

Name	Type	Required	Description
dataInput	textarea	Yes	—
inputFormat	select	Yes	—
keyFormat	select	Yes	—
delimiter	text	No	—
typeInference	select	Yes	—
arrayMode

MCP integration

Add this tool to your Model Context Protocol server so AI agents can list and call it.

Server configuration

Add this block to your MCP client configuration:

mcp.json

{
  "mcpServers": {
    "elysiatools-json-unflattener": {
      "name": "json-unflattener",
      "description": "Convert flattened key-value pairs back to nested JSON objects with support for different key formats and data type inference",
      "baseUrl": "https://api.elysiatools.com/mcp/sse?toolId=json-unflattener",
      "command": "",
      "args": [],
      "env": {},
      "isActive": true,
      "type": "sse"
    }
  }
}

List available tools

After connecting to the SSE endpoint, list the exposed tools:

tools/list

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/list"
}

Call this tool

Invoke the tool by its id, passing arguments built from its parameters:

tools/call

{
  "jsonrpc": "2.0",
  "id": 2,
  "method": "tools/call",
  "params": {
    "name": "json-unflattener",
    "arguments": {
  "dataInput": "{\n  \"user.name\": \"John\",\n  \"user.age\": \"30\",\n  \"user.city\": \"New York\",\n  \"settings.theme\": \"dark\",\n  \"settings.notifications\": \"true\"\n}",
  "inputFormat": "json",
  "keyFormat": "nested",
  "delimiter": ".",
  "typeInference": "auto",
  "arrayMode": "numeric",
  "mergeStrategy": "override",
  "preserveEmpty": true
}
  }
}

Chain multiple tools in one session with a comma-separated toolId list, e.g. /mcp/sse?toolId=png-to-webp,jpg-to-webp,gif-to-webp (max 20).

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