Unrecognized keys ${Object.keys(rest).join(', ')} found in p

Error message

Unrecognized keys ${Object.keys(rest).join(', ')} found in preset-classic configuration. The allowed keys are debug, docs, blog, pages, sitemap, theme, googleAnalytics, gtag, and googleTagManager. Check the documentation: https://docusaurus.io/docs/using-plugins#docusauruspreset-classic for more information on how to configure individual plugins.

What it means

Thrown by preset-classic when, after destructuring the known option keys (debug, docs, blog, pages, sitemap, svgr, theme, gtag, googleTagManager, googleAnalytics), the rest object still has keys. Any unrecognized top-level preset option is rejected and the allowed set is printed along with a docs link. Note 'svgr' is accepted by code though not listed in the message text.

Source

Thrown at packages/docusaurus-preset-classic/src/index.ts:108

  if (gtag) {
    plugins.push(makePluginConfig('@docusaurus/plugin-google-gtag', gtag));
  }
  if (googleTagManager) {
    plugins.push(
      makePluginConfig(
        '@docusaurus/plugin-google-tag-manager',
        googleTagManager,
      ),
    );
  }
  if (sitemap !== false && (isProd || debug)) {
    plugins.push(makePluginConfig('@docusaurus/plugin-sitemap', sitemap));
  }
  if (svgr !== false) {
    plugins.push(makePluginConfig('@docusaurus/plugin-svgr', svgr));
  }
  if (Object.keys(rest).length > 0) {
    throw new Error(
      `Unrecognized keys ${Object.keys(rest).join(
        ', ',
      )} found in preset-classic configuration. The allowed keys are debug, docs, blog, pages, sitemap, theme, googleAnalytics, gtag, and googleTagManager. Check the documentation: https://docusaurus.io/docs/using-plugins#docusauruspreset-classic for more information on how to configure individual plugins.`,
    );
  }

  return {themes, plugins};
}

export type {Options, ThemeConfig};

View on GitHub (pinned to 3f483e80e3)

Solutions

Remove or rename the unrecognized keys listed in the message to match an allowed key.
If the option targets a specific plugin, pass it under the correct sub-key (e.g. docs, blog, pages).
If it's a theme option, move it to themeConfig instead of the preset.

Example fix

// before
presets: [['classic', { doc: { sidebarCollapsed: false } }]]
// after
presets: [['classic', { docs: { sidebarCollapsed: false } }]]

Defensive patterns

Strategy: validation

Validate before calling

const allowed = new Set(['debug','docs','blog','pages','sitemap','svgr','theme','gtag','googleTagManager','googleAnalytics']);
const unknown = Object.keys(presetOptions).filter(k => !allowed.has(k));
if (unknown.length) throw new Error(`Unknown preset keys: ${unknown.join(', ')}`);

Prevention

Type preset options against the published Options type to catch typos at compile time.
Keep theme-only settings in themeConfig, not on the preset.

When it happens

Trigger: Passing a misspelled or removed preset option, e.g. presets: [['classic', { doc: {...} }]] (typo), or a removed option like 'googleAnalytics' after the v4 guard, or any extra key not in the allowed list.

Common situations: Typos (doc/docs, teme/theme); options from outdated tutorials; options that belong on themeConfig placed on the preset; leftover keys after upgrades.

Related errors

AI-assisted analysis of facebook/docusaurus@3f483e80e3 (2026-08-12). Data as JSON: /api/errors/aac4134ec34c0de4. Report an issue: GitHub.