Source authentic, high-res PUBLIC-DOMAIN artwork from museum open-access APIs (Met, Cleveland, SMK, Rijksmuseum, NGA, Art Institute of Chicago, Getty, Smithsonian) instead of AI-generated or generic-stock imagery. The default move whenever a visual needs an aesthetic, credible image (blog heroes, decks, social cards, essay/spec figures). Verified keyless recipes + licensing rules inside.
SkillScore95Maintained
Automatic
◆Marketing & Content pack
Last verified 8/14/2026
What it changes
Passed 20 of 21 test cases with the skill, and 14 of 21 without it.
Without skill68%
With skill95%
Checks it passed that the model alone missed
Formats the query string using repeated parameter keys for each filter bracket.
Identifies images.full.url as the response field containing the archival image asset.
Identifies the Rijksmuseum collection endpoint as the primary source for Dutch masters.
and 4 more in the full report
7 fixed14 passed either way0 still failing1 broke
Pass-rate lift
+27 pp
Tokens
+101%
Agent turns
0%
Response time
-39%
Model gemini-3.6-flashMeasured 8/14/2026v221 of 22 cases passed with skill · 21 comparable
Tokens, turns and time describe resource use, not a dollar price.
See it in action
One of 7 test cases the skill fixed. Same model, same prompt, with and without the skill.
1 of 7
Prompt
I am fetching image assets from the Cleveland Museum of Art Open Access API and need an uncompressed, archival-quality image file for high-dpi print production. Which field in the Cleveland API artwork response object contains this archival format URL?
What was checked, without and with the skill
Checked
Without skill
With skill
Identifies images.full.url as the response field containing the archival image asset.
Missed
Passed
case-08 · gemini-3.6-flash · 8/14/2026 · answers are capped and redacted
What's inside
The instructions your model reads when the skill loads.
SKILL.md93 lines10 files
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.
Use WebFetch to hit the JSON search endpoint, then WebFetch/download the returned image URL. These APIs are server-side reachable; no browser needed.
Exception - Art Institute of Chicago images: the JSON API (api.artic.edu) is fine, but the image host www.artic.edu/iiif/... 403s scripted/curl fetches via a Cloudflare bot challenge. Use the JSON metadata from AIC, but download the actual image through a real/headless browser (browser-harness) or prefer a different museum for the image bytes.
Always filter for public domain in the query AND spot-check the per-image license flag before shipping (see Licensing).
Freshness over caching (mandatory)
Fetch fresh per need. Do NOT build a reusable local pool of downloaded images to draw from. A small cached set gets reused everywhere and becomes the new "same stock photo on every post" - sameness is a form of slop, and the variety of a huge open collection is the entire point. Fetching is keyless and sub-second, so there is no cost reason to cache pixels.
Cache recipes/metadata, not images - that is what this skill's references/ already are.
Commit an image only into the specific artifact that uses it (a post's assets/, a deck's media) once chosen - for provenance and offline builds. That is an artifact asset, never a shared library other artifacts pull from.
Each new visual = a fresh query. Vary the search terms and the source museum so consecutive posts do not converge on the same few crowd-pleasers.
Verified keyless recipes (2026-07-24, all live-tested)
1. The Met - best all-around default
Base: https://collectionapi.metmuseum.org/public/collection/v1/ - no key, 80 req/s, CC0 where isPublicDomain:true.
Search: GET /search?q=<term>&hasImages=true&isPublicDomain=true -> {total, objectIDs[]}
Object: GET /objects/{id} -> read primaryImage (full-res JPEG, static, no IIIF hop) or primaryImageSmall (web-large).