curl --request POST \
  --url https://api.getoutbox.ai/agent/tool/{agent_id} \
  --header 'Authorization: <api-key>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "name": "<string>",
  "id": "<string>",
  "description": "<string>",
  "url": "<string>",
  "method": "POST",
  "type": "custom",
  "mcp_tool": "<string>",
  "auth_token": "<string>",
  "is_async": false,
  "is_success": false,
  "messages": [
    {
      "type": "request",
      "content": "<string>"
    }
  ],
  "schema": [
    {
      "id": "<string>",
      "name": "<string>",
      "description": "<string>",
      "type": "<string>",
      "required": true
    }
  ]
}
'