How It Works

The module main job is to tell robots (crawlers) how to behave.

Specifically, a main feature is to block Google from indexing pages that you don't want indexed.

Blocking Google from indexing pages is important for a number of reasons:

• Prevents duplicate content issues
• Prevents wasting crawling budget

While it does also attempt to control other robots, it is not always honored.

Robots.txt

For robots to understand how they can access your site, they will first check for a robots.txt file.

public
 └── robots.txt

This file is accessed differently depending on your environment:

• When deploying using nuxi generate or the nitro.prerender.routes rule, this is a static file.
• Otherwise, it's handled by the server and generated at runtime when requested.

When indexing is disabled a robots.txt will be generated with the following content:

User-agent: *
Disallow: /

This blocks all bots from indexing your site.

X-Robots-Tag Header and <meta name="robots">

In some situations, the robots.txt becomes too restrictive to provide the level of control you need to manage your site's indexing.

For this reason, the module by default will provide a X-Robots-Tag header and <meta name="robots"> tag.

These are applied using the following logic:

• X-Robots-Tag header - Route Rules are implemented for all modes, otherwise SSR only. This will only be added when indexing has been disabled for the route.
• <meta name="robots"> - SSR only, will always be added

Robot Rules

Default values for the robots rule depending on the mode.

For indexable routes the following is used:

<meta name="robots" content="index, follow, max-image-preview:large, max-snippet:-1, max-video-preview:-1">

Besides giving robots the go-ahead, this also requests that Google:

Choose the snippet length that it believes is most effective to help users discover your content and direct users to your site."

You can learn more on the Robots Meta Tag documentation, feel free to change this to suit your needs using robotsEnabledValue.

For non-indexable routes the following is used:

<meta name="robots" content="noindex, nofollow">

This will tell robots to not index the page.

Development Environment

The module by default will disable indexing in development environments. This is for safety, as you don't want your development environment to be indexed by search engines.

# Block all bots
User-agent: *
Disallow: /

Production Environments

For production environments, the module will generate a robots.txt file that allows all bots.

Out-of-the-box, this will be the following:

User-agent: *
Disallow:

This tells all bots that they can index your entire site.