Runtime.ExecutionContextDescription

{
  "id": "ExecutionContextDescription",
  "type": "object",
  "description": "Description of an isolated world.",
  "properties": [
    {
      "name": "id",
      "$ref": "ExecutionContextId",
      "description": "Unique id of the execution context. It can be used to specify in which execution context script evaluation should be performed."
    },
    {
      "name": "isPageContext",
      "type": "boolean",
      "description": "True if this is a context where inpspected web page scripts run. False if it is a content script isolated context."
    },
    {
      "name": "name",
      "type": "string",
      "description": "Human readable name describing given context."
    },
    {
      "name": "frameId",
      "$ref": "Network.FrameId",
      "description": "Id of the owning frame."
    }
  ]
}