@@ -0,0 +1,67 @@
+name: Monthly thumbnail refresh
+
+# On the first of each month: re-fetch the publisher previews that are due
+# (older than 180 days, licence changed, or new eligible entries), push the
+# changed files to a thumbs/<month> branch and open or update one issue with
+# the compare link. The repository does not let Actions open pull requests,
+# and a token-made pull request would not run CI, so the maintainer opens it
+# from the link. It never edits an entry. Rules: site/lib/thumbs.mjs.
+on:
+  schedule:
+    - cron: "0 9 1 * *"
+  workflow_dispatch:
+
+permissions:
+  contents: write
+  issues: write
+
+jobs:
+  thumbs:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+
+      - name: Setup Node
+        uses: actions/setup-node@949feb2413d6458794dcd2491c4babbbce0c15c1 # v7.1.0
+        with:
+          node-version-file: .nvmrc
+
+      - name: Ensure ffmpeg
+        run: |
+          if ! command -v ffmpeg >/dev/null 2>&1; then
+            sudo apt-get update -qq && sudo apt-get install -y -qq ffmpeg
+          fi
+          ffmpeg -version | head -1
+
+      - name: Fetch and resize previews
+        id: run
+        run: node site/thumbs.mjs --report thumbs-report.md
+
+      - name: Validate the result
+        run: node site/validate.mjs
+
+      - name: Push the branch and open or update the issue
+        if: steps.run.outputs.changed != '0'
+        env:
+          GH_TOKEN: ${{ github.token }}
+          CHANGED: ${{ steps.run.outputs.changed }}
+        run: |
+          month=$(date -u +%Y-%m)
+          branch="thumbs/${month}"
+          git config user.name "github-actions[bot]"
+          git config user.email "41898282+github-actions[bot]@users.noreply.github.com"
+          git switch -c "$branch"
+          git add site/thumbs.json site/public/thumbs
+          git commit -m "thumbs: monthly refresh ${month} (${CHANGED} changes)"
+          git push --force origin "$branch"
+          compare="https://github.com/${GITHUB_REPOSITORY}/compare/main...$(printf '%s' "$branch" | sed 's|/|%2F|g')?expand=1"
+          { printf 'Open the pull request: %s\n\n' "$compare"; cat thumbs-report.md; } > issue-body.md
+          title="Thumbnail refresh ${month}: ${CHANGED} changes"
+          existing=$(gh issue list --state open --label "enhancement" --json number,title \
+            --jq '[.[] | select(.title | startswith("Thumbnail refresh "))][0].number // empty')
+          if [ -n "$existing" ]; then
+            gh issue edit "$existing" --title "$title" --body-file issue-body.md
+          else
+            gh issue create --title "$title" --label "enhancement" --body-file issue-body.md
+          fi
@@ -85,6 +85,12 @@ with no code.
 
 Publishers are welcome to list their own work. Say so in the pull request, write the entry as a third party would (facts the source states, no comparisons with other entries, no ranking language), and start it at `needs-review` so a maintainer re-reads the licence before it goes `active`. A free tier of a paid product is listed as the free tier only, with the paid tier named in Notes and not linked as the entry's `url`. A one-time notice or upsell inside a tool is recorded in Notes as a fact.
 
+## Preview images
+
+The site shows each entry's preview image where it can. The picture is the publisher's own `og:image` from the entry's `url`, fetched by `npm run thumbs`, resized to 640 pixels wide and committed under `site/public/thumbs/` with a record in `site/thumbs.json`. Only `active` entries whose licence is on the allowlist in `site/lib/thumbs.mjs` (CC0, CC-BY, MIT, OFL, GPL and the other open licences that allow a resized copy) get one; `custom`, `varies` and `unknown` never do, and neither do GitHub repositories, whose social card is not a preview. The validator fails when a committed image no longer passes that gate, and the script removes it on its next run.
+
+A publisher who would rather not have their preview shown can open an issue; the maintainer sets `preview: none` on the entry and the image is removed. A maintainer who has checked that a specific image is covered by the entry's licence can set `preview: https://...` to use that image instead of the page's `og:image`.
+
 ## Automated and AI-assisted pull requests
 
 Changes drafted with an agent or a script are judged on the diff like any other. Keep them small, keep tests in `site/checks.test.mjs` or `site/lib/lib.test.mjs` (a test file that `npm test` does not run is dropped), and name the issue the change fixes in the body (`Fixes #N`). A pull request that lists sources or licences the author did not read is closed: the catalog's one rule is that every licence fact was read at the source by the person who recorded it.
 
@@ -21,6 +21,7 @@ verified: 2026-07-19
 status: needs-review
 # Optional (omit if N/A):
 # publisher: Kenney   # rights holder when that publisher has more than one entry; not a generic host
+# preview: none   # or an https:// image URL a maintainer has checked; see CONTRIBUTING.md "Preview images"
 # attribution_string: "Credit line"   # required when attribution_required is true
 # commercial: varies   # aggregators only; not a blanket commercial grant
 # grid_dimensions: 16x16          # 2D and UI entries only
 
@@ -1,36 +1,37 @@
----
-id: blender-ellie-poses
-name: Blender Studio Ellie Pose Library
-url: https://www.blender.org/download/demo-files/#assets
-publisher: Blender Studio
-category: animation
-subcategories: [poses, rigging]
-license: CC-BY
-commercial: true
-attribution_required: true
-attribution_string: "Ellie Pose Library (c) Blender Studio. CC-BY. Suggested format; card does not specify wording."
-formats: [Blend]
-tags: [poses]
+---
+id: blender-ellie-poses
+name: Blender Studio Ellie Pose Library
+url: https://www.blender.org/download/demo-files/#assets
+publisher: Blender Studio
+category: animation
+subcategories: [poses, rigging]
+license: CC-BY
+commercial: true
+attribution_required: true
+attribution_string: "Ellie Pose Library (c) Blender Studio. CC-BY. Suggested format; card does not specify wording."
+formats: [Blend]
+tags: [poses]
+preview: none   # the page's og:image is the publisher's general promo, not this pack
 added: 2026-07-19
-verified: 2026-08-24
-status: active
----
-
-# Blender Studio Ellie Pose Library
-
-Humanoid pose library from Blender Studio. The verified card on the [demo-files](https://www.blender.org/download/demo-files/#assets) listing is **Ellie Pose Library v2.0.0** (Asset Bundles section, 24 MB, CC-BY). That listing mixes CC0 and CC-BY cards on one page; this entry is only the Ellie card, not Cube Diorama or Human Base Meshes.
-
-## Notes
-
-- Direct zip (v2.0.0, Blender 4.0+): listed `url`. Version bumps change the filename; re-check the Asset Bundles card if the zip 404s.
-- License evidence lives on the demo-files listing, not inside the zip.
-- Attribution example: `Ellie Pose Library © Blender Studio — CC-BY`
-
-## Evidence
-
-- Live [Demo Files](https://www.blender.org/download/demo-files/) (2026-08-24): "CC-BY" on the Ellie Pose Library card (24 MB, Blender Studio)
-
-## Related
-
-- [cmu-mocap](cmu-mocap.md)
-- [mixamo](mixamo.md)
+verified: 2026-08-24
+status: active
+---
+
+# Blender Studio Ellie Pose Library
+
+Humanoid pose library from Blender Studio. The verified card on the [demo-files](https://www.blender.org/download/demo-files/#assets) listing is **Ellie Pose Library v2.0.0** (Asset Bundles section, 24 MB, CC-BY). That listing mixes CC0 and CC-BY cards on one page; this entry is only the Ellie card, not Cube Diorama or Human Base Meshes.
+
+## Notes
+
+- Direct zip (v2.0.0, Blender 4.0+): listed `url`. Version bumps change the filename; re-check the Asset Bundles card if the zip 404s.
+- License evidence lives on the demo-files listing, not inside the zip.
+- Attribution example: `Ellie Pose Library © Blender Studio — CC-BY`
+
+## Evidence
+
+- Live [Demo Files](https://www.blender.org/download/demo-files/) (2026-08-24): "CC-BY" on the Ellie Pose Library card (24 MB, Blender Studio)
+
+## Related
+
+- [cmu-mocap](cmu-mocap.md)
+- [mixamo](mixamo.md)
@@ -1,39 +1,40 @@
----
-id: blender-human-base-meshes
-name: Blender Studio Human Base Meshes
-url: https://www.blender.org/download/demo-files/#assets
-publisher: Blender Studio
-category: characters
-subcategories: [base-meshes]
-license: CC0
-license_spdx: CC0-1.0
-commercial: true
-attribution_required: false
-formats: [Blend, glTF, FBX]
-tags: [topology]
+---
+id: blender-human-base-meshes
+name: Blender Studio Human Base Meshes
+url: https://www.blender.org/download/demo-files/#assets
+publisher: Blender Studio
+category: characters
+subcategories: [base-meshes]
+license: CC0
+license_spdx: CC0-1.0
+commercial: true
+attribution_required: false
+formats: [Blend, glTF, FBX]
+tags: [topology]
+preview: none   # the page's og:image is the publisher's general promo, not this pack
 added: 2026-07-19
-verified: 2026-08-24
-status: active
----
-
-# Blender Studio Human Base Meshes
-
-Production topology humanoid scaffolds from Blender Studio. The verified card on the [demo-files](https://www.blender.org/download/demo-files/#assets) listing is **Human Base Meshes v1.4.1** (Asset Bundles section, 49 MB, CC0). That listing mixes CC0 and CC-BY cards on one page; Ellie Pose Library on the same section is CC-BY and is a different entry. Export glTF/FBX for engines. Confirm the badge still says CC0 if the version number moves.
-
-## Notes
-
-- Direct zip (v1.4.1, Blender 4.2 LTS+): listed `url`. Version bumps change the filename; re-check the Asset Bundles card if the zip 404s.
-- Same demo-files listing as [blender-ellie-poses](../animation/blender-ellie-poses.md). Ellie is CC-BY; this bundle is CC0. Do not mix the two grants.
-
-## Evidence
-
-- Live Demo Files (2026-08-24): Human Base Meshes v1.4.1 card "49 MB - CC0"
-
-## Related
-
-- [../animation/blender-ellie-poses](../animation/blender-ellie-poses.md)
-- [blender-studio-rain](blender-studio-rain.md)
-- [blender-studio-one](blender-studio-one.md)
-- [blender-studio-critter](blender-studio-critter.md)
-- [makehuman](makehuman.md)
-- [../3d/the-base-mesh](../3d/the-base-mesh.md)
+verified: 2026-08-24
+status: active
+---
+
+# Blender Studio Human Base Meshes
+
+Production topology humanoid scaffolds from Blender Studio. The verified card on the [demo-files](https://www.blender.org/download/demo-files/#assets) listing is **Human Base Meshes v1.4.1** (Asset Bundles section, 49 MB, CC0). That listing mixes CC0 and CC-BY cards on one page; Ellie Pose Library on the same section is CC-BY and is a different entry. Export glTF/FBX for engines. Confirm the badge still says CC0 if the version number moves.
+
+## Notes
+
+- Direct zip (v1.4.1, Blender 4.2 LTS+): listed `url`. Version bumps change the filename; re-check the Asset Bundles card if the zip 404s.
+- Same demo-files listing as [blender-ellie-poses](../animation/blender-ellie-poses.md). Ellie is CC-BY; this bundle is CC0. Do not mix the two grants.
+
+## Evidence
+
+- Live Demo Files (2026-08-24): Human Base Meshes v1.4.1 card "49 MB - CC0"
+
+## Related
+
+- [../animation/blender-ellie-poses](../animation/blender-ellie-poses.md)
+- [blender-studio-rain](blender-studio-rain.md)
+- [blender-studio-one](blender-studio-one.md)
+- [blender-studio-critter](blender-studio-critter.md)
+- [makehuman](makehuman.md)
+- [../3d/the-base-mesh](../3d/the-base-mesh.md)
@@ -1,39 +1,40 @@
----
-id: kenney-animated-characters
-name: Kenney Animated Characters
-url: https://kenney.nl/assets?series=Animated+Characters
-publisher: Kenney
-category: characters
-subcategories: [rigged, animated, humanoid]
-license: CC0
-license_spdx: CC0-1.0
-commercial: true
-attribution_required: false
-formats: [FBX, PNG, SVG]
-tags: [low-poly, survivors, zombie, skins]
+---
+id: kenney-animated-characters
+name: Kenney Animated Characters
+url: https://kenney.nl/assets?series=Animated+Characters
+publisher: Kenney
+category: characters
+subcategories: [rigged, animated, humanoid]
+license: CC0
+license_spdx: CC0-1.0
+commercial: true
+attribution_required: false
+formats: [FBX, PNG, SVG]
+tags: [low-poly, survivors, zombie, skins]
+preview: none   # the page's og:image is the publisher's general promo, not this pack
 added: 2026-09-26
-verified: 2026-09-26
-status: active
----
-
-# Kenney Animated Characters
-
-Kenney's "Animated Characters" series: three small packs of rigged, animated low-poly humanoids with swappable PNG skins. [Protagonists](https://kenney.nl/assets/animated-characters-protagonists) (2020; skater, cyborg, criminal), [Retro](https://kenney.nl/assets/animated-characters-retro) (2022) and [Survivors](https://kenney.nl/assets/animated-characters-survivors) (2019; zombie and survivor). All three are CC0.
-
-## Notes
-
-- One entry for the series, since each pack is the same rig and format with different skins
-- Contents read from each pack's download ZIP (2026-09-26): 4 FBX files plus PNG skins in each, and SVG files in Protagonists and Survivors
-- The bundled `License.txt` says credit is welcome but "not a requirement"
-- Attribution example (optional): `Characters by Kenney.nl (CC0)`
-
-## Evidence
-
-- Live pack pages for Protagonists, Retro and Survivors (2026-09-26): each shows Category "3D", series "Animated Characters", 8 files, License "Creative Commons CC0"
-- `License.txt` in the Protagonists download (2026-09-26): "License: (Creative Commons Zero, CC0)", "You can use this content for personal, educational, and commercial purposes. Support by crediting 'Kenney' or 'www.kenney.nl' (this is not a requirement)"
-
-## Related
-
-- [kaykit-adventurers](kaykit-adventurers.md)
-- [quaternius-universal-base-characters](quaternius-universal-base-characters.md)
-- [kenney](../3d/kenney.md)
+verified: 2026-09-26
+status: active
+---
+
+# Kenney Animated Characters
+
+Kenney's "Animated Characters" series: three small packs of rigged, animated low-poly humanoids with swappable PNG skins. [Protagonists](https://kenney.nl/assets/animated-characters-protagonists) (2020; skater, cyborg, criminal), [Retro](https://kenney.nl/assets/animated-characters-retro) (2022) and [Survivors](https://kenney.nl/assets/animated-characters-survivors) (2019; zombie and survivor). All three are CC0.
+
+## Notes
+
+- One entry for the series, since each pack is the same rig and format with different skins
+- Contents read from each pack's download ZIP (2026-09-26): 4 FBX files plus PNG skins in each, and SVG files in Protagonists and Survivors
+- The bundled `License.txt` says credit is welcome but "not a requirement"
+- Attribution example (optional): `Characters by Kenney.nl (CC0)`
+
+## Evidence
+
+- Live pack pages for Protagonists, Retro and Survivors (2026-09-26): each shows Category "3D", series "Animated Characters", 8 files, License "Creative Commons CC0"
+- `License.txt` in the Protagonists download (2026-09-26): "License: (Creative Commons Zero, CC0)", "You can use this content for personal, educational, and commercial purposes. Support by crediting 'Kenney' or 'www.kenney.nl' (this is not a requirement)"
+
+## Related
+
+- [kaykit-adventurers](kaykit-adventurers.md)
+- [quaternius-universal-base-characters](quaternius-universal-base-characters.md)
+- [kenney](../3d/kenney.md)