{
  "source": "src",
  "destination": "dist",
  "plugins": {
    "metalsmith-broken-link-checker": true,
    "metalsmith-drafts": true,
    "metalsmith-assets": {
      "source": "./assets",
      "destination": "."
    },
    "metalsmith-markdown": {
      "smartypants": true,
      "gfm": true,
      "tables": true
    },
    "metalsmith-layouts": {
      "engine": "handlebars",
      "directory": "src/template/layouts",
      "partials": "src/template/partials",
      "pattern": "pages/**/*"
    },
    "metalsmith-move-up": {
     "pattern": [
      "pages/**",
      "images/favicon.ico"
    ]
    },
    "metalsmith-ignore": [
      "drafts/*",
      "unfinished/*"
    ]
  }
}

{
  "source": "src",
  "destination": "dist",
  "plugins": {
    "metalsmith-broken-link-checker": {
      "allowRedirects": true,
      "warn": true
    },
    "metalsmith-drafts": true,
    "metalsmith-assets": {
      "source": "./assets",
      "destination": "."
    },
    "metalsmith-markdown": {
      "smartypants": true,
      "gfm": true,
      "tables": true
    },
    "metalsmith-layouts": {
      "engine": "handlebars",
      "directory": "src/template/layouts",
      "partials": "src/template/partials",
      "pattern": "pages/**/*"
    },
    "metalsmith-move-up": {
     "pattern": [
      "pages/**",
      "images/favicon.ico"
    ]
    },
    "metalsmith-ignore": [
      "drafts/*",
      "unfinished/*"
    ]
  }
}

Change configuration of broken link checker to output warn
Change configuration of broken link checker to output warn
