{
  "openapi": "3.0.1",
  "info": {
    "title": "RestRserve OpenAPI",
    "version": "1.0"
  },
  "servers": [
    {
      "url": "/"
    }
  ],
  "paths": {
    "/fib": {
      "get": {
        "description": "Calculates Fibonacci number",
        "parameters": [
          {
            "name": "n",
            "description": "x for Fibonnacci number",
            "in": "query",
            "schema": {
              "type": "integer"
            },
            "example": 10,
            "required": true
          }
        ],
        "responses": {
          "200": {
            "description": "API response",
            "content": {
              "text/plain": {
                "schema": {
                  "type": "string",
                  "example": 5
                }
              }
            }
          },
          "400": {
            "description": "Bad Request"
          }
        }
      }
    }
  }
}