vue-cli-plugin-axios-ts/generator/templates/plugins/index.d.ts

Vue-cli-3 plugin: axios for ts

import Vue, { VueConstructor } from 'vue';
import { AxiosInstance } from 'axios';

declare global {
  interface Window {
    axios: AxiosInstance
  }
}

declare module 'vue/types/vue' {
  interface Vue {
    $axios: AxiosInstance
  }
  interface VueConstructor {
    $axios: AxiosInstance
  }
}