Uwawp What an AI API key adds to Ariadne’s matching, and what happens if you don’t have one.
What it adds
Without an AI key, Ariadne still matches posts well — shared tags, shared categories, title overlap, and local text similarity all work normally, with no external service involved. An AI key adds one more layer on top: understanding what a post is actually about, not just which words it contains.
Two posts can be strongly related in meaning while sharing almost no vocabulary — a piece about “reducing server response time” and one about “why your website feels slow” are the same topic in different words. Local text matching alone won’t connect them reliably; semantic matching will.
Do you need one?
If your content is well-tagged and categorized, and posts on the same topic tend to use similar language, local matching alone (the Free tier) already performs well. An AI key is worth adding when:
- Your site covers a topic from many different angles or in different phrasing
- Tags and categories aren’t consistently applied across your archive
- You want the related-list quality to keep improving as your matching weights shift, without depending entirely on exact wording
How it works, and what it costs
Ariadne calls the AI service (Voyage AI) exactly once per post — when that post is saved, and only if its content has actually changed since the last time. Nothing is ever called while a visitor is viewing your site; all comparisons at read time are a local, already-computed lookup. This keeps the ongoing cost predictable and tied to how much you publish, not how much traffic you get.
Setting it up
Once you’re on a Pro or Pro+ plan:
- Get an API key from Voyage AI.
- Add it either as
define( 'ARP_VOYAGE_API_KEY', 'your-key-here' );inwp-config.php(recommended, keeps it out of the database), or paste it into the field on Settings → Ariadne Related Posts. - Save. Existing posts pick up semantic matching gradually, in the background, without you needing to trigger anything — a fresh install processes its whole archive the same way, a few posts at a time.
If you’d rather speed that initial pass along, the Post Status screen has a manual “catch up now” action. See command-line automation for a scriptable equivalent.