museum-art: Public-Domain Artwork for Visuals

Standing rule (adopted 2026-07-24, from Eric Li's post on museum open-access): whenever a visual needs a real image with aesthetic weight, source public-domain museum artwork first - over AI-generated imagery and over generic stock. Curated, historically significant art reads as credible and sophisticated; AI-gen reads as slop. This stacks with, and reinforces, the no-ai-slop skill and your house image style. It does NOT replace the generative editorial-illustrations skill (that owns claim-driven diagrams/figures) or your house chart style - use museum art for photographic/hero/decorative/mood imagery, generative figures for data and concept diagrams.

When to reach for this

Blog post hero images, section breaks, mood imagery (the blog-publish image step).
Deck/slide backgrounds and section dividers, social cards, essay figures, spec cover art.
Any time the instinct is "generate an image" for something decorative or evocative. Stop and pull a real painting instead.
NOT for: product screenshots, UI mockups, data charts, logos, or claim-driven explanatory diagrams (those are editorial-illustrations / real captures).

Decision: which source

Met -> Cleveland -> SMK first. All keyless, one JSON hop, CC0/PD, broad collections. Fastest path to a hi-res image.
Need Dutch/Flemish masters or decorative arts? Rijksmuseum (keyless, 3 hops).
Need European antiquities/photography and keyword isn't essential? Getty (keyless, SPARQL).
Nothing fits, or you want a cross-museum search? Wikimedia Commons API (keyless aggregator, normalized license metadata) is the best general fallback.
"Historical illustration/engraving/old photo" rather than fine-art painting? Go straight to Internet Archive or Wikimedia Commons.
Science/health/medical essay figure? Wellcome Collection (keyless, CC0/PD).