Any type definition for the promise returned?

[akdotio]

Is there any type of definition for the promise returned?

for example

componentDidMount() {
    this.props.loadCategories().then(res => {
      // what is the type of res
    })
  }

I wanna represent the res with a typescript interface, so I came up with the following representation

/**
 * Describes the returned object of axios middleware action creators
 */
export interface IAxiosAction<TData = any> {
  type: string
  payload: {
    request: {
      client: string
      method: string
      url: string
    }
  }
}

/**
 * Describes the returned object of axios middleware calls
 */
export interface IAxiosResult<TData = any> {
  type: string
  payload: {
    config: IAxiosRequestConfig
    data: TData
    headers: { [key: string]: string }
    request: XMLHttpRequest
    status: number
    statusText: string
  }
  meta: {
    previousAction: IAxiosAction<TData>
  }
}

/**
 * Describes request config object of axios calls
 */
export interface IAxiosRequestConfig<TData = any> {
  adapter: any
  baseURL: string
  client: string
  data?: TData
  headers: { [key: string]: string }
  maxContentLength: number
  method: string
  reduxSourceAction: IAxiosAction<TData>
  responseType: string
  timeout: number
  transformRequest: any
  transformResponse: any
  url: string
  validateStatus: any
  xsrfCookieName: string
  xsrfHeaderName: string
}

Are the interfaces above really describes the res object? if so are you open to add .d.ts definition files to your source code?