Structural error at paths./

Completely new to Swagger, and I'm getting the error in the subject for the following JSON code (btw, this example of code is basically copied from a swagger created by an "expert" here at work. Trouble is, their code also fails the swagger editor test in the same way.

{
    "swagger": "2.0",
    "info": {
        "title": "--API-title--",
        "version": "1.0.0",
        "description": " --API-description--"
    },
    "host": "our.host.at.work",
    "basePath": "/my/basepath",
    "schemes": [
        "https"
    ],
    "paths": 
    {
        "/": {
            "GET": {
                "tags": [
                    "JPB261"
                ],
                "summary": "",
                "description": "endpoint desc",
                "produces": [
                    "application/json"
                ],
                "parameters": [

The error message I'm getting is

Structural error at paths./

should NOT have additional properties additionalProperty: GET