What are random links in the Internal Links API response?

When there are not enough related links available to link to, the API will have the following message:

"message": "Not enough related links; returning related and random links

This is denoted in the related links response as "type": "random"

These links we refer to as SEO links, as they are optimized for link spread.

When we build an API endpoint, we are optimizing link spread for the number of links requested. For example, if an API endpoint with 9 links is requested, we are optimizing for link spread so that each page receives the maximum number (9) internal (inbound links) per page.

Our API endpoints are built to optimize both for relatedness and for link spread. We will return as many related links to the source page as possible. Any remaining links that do not have enough related pages available, we will return an SEO link. This is not a truly “random” page being returned. Instead, we are looking for pages that don’t yet have a sufficient amount of internal links available to reach the maximum (9 from the example) and returning SEO link(s) to have as equitable amount of link spread as possible. This provides opportunities with Google for faster indexation, improved crawl budget, and improved traffic.
See Case Study. See AB Test.

Graphite does not advise replacing SEO links with other links or ignoring SEO links during implementation. This can have the potential to decrease the link spread that the API was built to achieve and negatively affect the growth potential of the SEO links (pages) that are being removed or replaced.

One of the differentiators behind Graphite’s Internal Links API and typical related linking modules, that allows for increases in traffic growth, is the SEO optimization the API provides through SEO linking.

Please keep in mind that generally, the larger a site section is, typically less SEO links are needed in order to achieve the ideal amount of link spread, as there are generally a greater number of pages available to link to that are related, also optimizing for the link spread.