Multimodal - AI-readiness signals
All 16 signals in the Multimodal category, with what each tests and why it matters for visibility in AI.
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VideoObject structured data with transcript on every video page
Tell AI systems that your page hosts video, and hand them the transcript text.
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AudioObject markup with transcript on every audio-bearing page
Give AI systems a structured pointer to your audio plus the spoken text.
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PodcastSeries and PodcastEpisode markup with feed and transcripts
Make podcast content machine-readable across episodes, series, and the underlying RSS feed.
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Image sitemap extension covering content images across your site
Tell AI image search and visual crawlers where every important image on your site lives.
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Video sitemap extension with thumbnail, title, description, and player URL
Give AI crawlers a direct inventory of analysable video without relying on JavaScript players.
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WebVTT caption and subtitle tracks on every HTML video
Publish time-aligned plain-text captions any crawler can fetch alongside your video.
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Limit text trapped inside images to a small share of the page
Keep meaningful text as real HTML so AI can read it without expensive optical character recognition.
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MathML markup for equations on STEM and technical pages
Encode formulas as structured MathML rather than rasterised images or raw LaTeX strings.
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Descriptive, hyphenated filenames on content images
Use human-readable image filenames so URL paths add semantic context for AI crawlers.
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Responsive images via srcset and picture for modern crawlers
Offer multiple resolutions so AI vision pipelines can pick the high-quality variant.
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AVIF or WebP served on a meaningful share of raster images
Modern image formats give crawlers more visual fidelity per byte ingested.
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Correct loading and decoding hints on above- and below-fold images
Lazy-load images below the fold, but never the hero, so non-JavaScript crawlers see your content.
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Image Content-Type header matches the file's actual format
Make sure your server tells the truth about what kind of image it is serving.
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Alt text embedded inside image files via IPTC metadata
Bake descriptive text into the image binary so it survives CDNs, re-hosting, and copying.
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ARIA labels on custom video and audio player controls
If your media player is custom-built, every button needs an accessible name.
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PDFs tagged with structure, language, and document title
Linked PDFs need accessibility tagging so AI can extract the text in the right reading order.