Out of the box the free plugin writes alt text, title, filename and keywords for every image. Pro adds two more: the WordPress caption and the WordPress description. They’re standard WP fields — the same ones the Media Library uses — but having the AI fill them too rounds out an image’s metadata for themes and page builders that surface them visibly.
What they map to in WordPress
WordPress field mapping
| Feature | Where it's stored | Where it's visible to readers |
|---|---|---|
| Caption Short, visible. | WP attachment’s post_excerpt — the same field as Media Library → Caption. | Image block captions in posts, gallery captions, some lightbox plugins. |
| Description Longer, narrative. | WP attachment’s post_content — the same field as Media Library → Description. | Auto-generated attachment pages, some lightboxes, some rich-preview generators that fall back to attachment metadata. |
Native fields, not custom storage
The plugin doesn’t maintain its own caption / description tables. Anything Pro writes here is visible immediately in Media Library → Edit attachment, accessible to your theme and any other plugin reading attachment metadata. If you stop using Pro, the fields stay populated — no lock-in.
When to use which
Caption vs description
| Feature | Best for | Tone & length |
|---|---|---|
| Caption Written to be seen. | Image blocks that show captions to readers (Gutenberg image block with caption, gallery items, some lightbox plugins). | One or two short sentences. Voice your readers actually see — match your site’s tone closely. |
| Description Longer, more narrative. | Attachment pages, lightboxes that show long copy, rich previews that fall back to description metadata. | Two to four sentences. More room to add context, history or specifications — still natural-language, not a keyword stuff. |
Context Summary — make the AI smarter
Generating a caption from an image alone gives the AI very little to work with — it sees pixels but doesn’t know the surrounding article is about Mediterranean cooking or 18th-century architecture. Pro’s Context Summary feature lets the AI peek at the surrounding content.
Open the Caption or Description modal
Click the Caption or Description column on any row to open the editor. Inside each modal you’ll see a Context Summary section near the top.
Click “Generate Context”
The plugin uses the Image Usage tracker to find every page the image is embedded in, pulls in the surrounding text, and summarises it — handing the summary to the AI alongside the image.
Click Optimize with AI
With the context in hand, the AI writes a caption / description that actually reflects the image’s role on the page, not just its visual content. Much better results on news photography, product detail shots, and any image whose meaning is page-dependent.
Where to edit and bulk-run them
Modal: Caption Editor
The dedicated caption editor with character counter and AI suggestion.
Modal: Description Editor
The longer-form description editor for narrative copy.
Real-time Upload Optimization
Generate captions and descriptions automatically as soon as you upload an image.