validate-screenshots

name	validate-screenshots
description	Validates PNG screenshots in an OutSystems docs article against the team's visual rules (highlight components, shadow, cursor, naming, cropping). Returns a short issues-only summary so the content developer knows whether the images are ready for design review. Use when a content developer wants to check their screenshots before merging, or asks to "review screenshots", "check my screenshots", "validate screenshots", "screenshot review". Trigger phrases: "validate screenshots", "review screenshots", "check my screenshots", "are these screenshots good", "screenshot review".
allowed-tools	Read,Bash,Edit,AskUserQuestion
metadata	{"exclude-repos":["OutSystems/training-internal"]}

Validate screenshots

Runs a design-system review on PNG screenshots a content developer added to an OutSystems docs article, so they can self-check before asking for manual design review.

The rubric lives in visual-rules-screenshots.md next to this file — it is produced by running scripts/calibrate.py against a reference set of approved screenshots. If that file is still a placeholder, stop and tell the user to run calibration first (see the Calibration section below).

Setup

Read visual-rules-screenshots.md from the same directory as this SKILL.md. If it still contains the placeholder marker (<!-- NOT CALIBRATED -->), stop and print:

"No screenshot rubric yet. Run scripts/calibrate.py once with a set of approved screenshots to generate visual-rules-screenshots.md, then try again."

Step 1: Resolve targets

Call the target collector with whatever the user passed (default to empty):

python3 -B <skill-dir>/scripts/collect_targets.py "$ARGUMENTS"

It prints a JSON array to stdout. Each entry has:

• image_path — absolute path to the PNG
• article_path — the markdown that references it, or null

If the array is empty, stop with:

"No screenshots to validate. Pass a markdown file, a PNG path, or run without arguments on a branch that has image changes vs. master."

Duplicate detection

After collecting targets, group entries by their sha256 field. If two or more entries share a hash, the files are byte-for-byte identical and only one copy should exist. Mark every duplicate with a ❌ finding in the final summary:

"Byte-identical duplicate of <other image name>. Keep one and delete the rest."

Empty sha256 values (file unreadable) are not grouped.

Step 2: Validate each target

For each entry in the list:

1. Read the image with the Read tool so it goes into vision.

2. Run the deterministic checkers. They are authoritative for the rules they cover — do not second-guess them from vision.

   python3 -B <skill-dir>/scripts/check_metadata.py "<image_path>"
   python3 -B <skill-dir>/scripts/has_shadow.py    "<image_path>"
   python3 -B <skill-dir>/scripts/check_red.py     "<image_path>"
   

   • check_metadata.py prints JSON covering rule 1 (PNG format), rule 2 (filename regex + surface suffix, including double-suffix detection), and rule 10 (width ≤ 1200 px). Parse the JSON and use each verdict directly.
   • has_shadow.py prints one of shadow: true / shadow: wrong / shadow: false / shadow: inconclusive / shadow: unknown for rule 6. Map them to severity as follows: true passes. wrong is ❌ — output exactly this text (do not paraphrase): "Shadow doesn't match the TK-shadow effect available in the TK design library — apply it from the Effects menu in Figma (rule 6)". false is ❌ for large-surface captures and ⚠️ otherwise — never a clean pass, so the reviewer always sees it and can dismiss when it's genuinely a self-bounded close crop. Output exactly this text (do not paraphrase): "Missing TK-shadow effect available in the TK design library — apply it from the Effects menu in Figma (rule 6)". inconclusive is ⚠️ — the alpha channel is present but the detector couldn't reach opaque content on the sampled edges (e.g. content far from the borders, transparent mid-edges). Output exactly this text (do not paraphrase): "Shadow check inconclusive — designer should verify the TK-shadow effect available in the TK design library (Effects menu in Figma) is applied (rule 6)". Do not restate it as "missing shadow" — the script didn't say that. unknown means the image has no alpha channel at all (typically a JPG saved as .png, which rule 1 already fails); don't emit a separate shadow finding in that case. Do not suppress a false verdict based on your own close-crop judgment — surface it as ⚠️ at minimum. Refer to rule 6 in the rubric for the full definitions.
   • check_red.py prints one of red: ok #RRGGBB / red: wrong #RRGGBB (token #F22800) / red: none for the color half of rule 3. Map it as: ok passes; none passes (the image has no red highlight, so there's nothing to color-check); wrong is ⚠️ — phrase as "Highlight red is #RRGGBB, not the design-system token #F22800 — re-snap from the Figma library", quoting the actual hex from the script so the user can confirm. Vision can't reliably distinguish similar reds (#F22800 vs #CC2200 vs #BB1F00), so do not second-guess the script.

3. Use vision only for the rules the scripts don't cover: rule 2's suffix-vs-content mismatch (filename says -ss but the image shows ODC Studio), rule 3's placement (whether a highlight is present and on the right element — the color is scripted), rule 4 (numbered callouts), rule 5 (arrows), rule 7 (cursor — skip if the screenshot already has numbered callouts; they substitute for the cursor in step-based flows), rule 8 (PII), rule 9 (internal environment URLs).

   For files ending in -diag: use vision to determine whether the content is a genuine diagram or a UI screenshot.

   A genuine diagram has all of the following:

   • No product UI chrome (no IDE toolbars, portal navigation, or browser address bar)
   • A conceptual layout: flow chart, sequence diagram, hierarchy tree, architecture box, icon grid, or swimlane diagram
   • OutSystems branded orange/red iconography representing concepts
   • Connecting elements: arrows, dashed lines, or swimlanes
   • A white or light-gray background with a rounded-rectangle shadow border
   • Descriptive text labels naming concepts or roles, not UI controls

   A UI screenshot shows product interface chrome with interactive elements (panels, toolbars, dropdowns, form fields, menus) from ODC Studio, ODC Portal, Service Studio, or similar tools.

   • If the content is a genuine diagram → suffix is correct; no naming finding.
   • If the content is a UI screenshot → emit ❌ Rule 2: "Image looks like a UI screenshot but uses the -diag suffix — rename with the correct surface suffix (e.g. -ss, -odcs)."

4. Collect only failures and warnings — passing rules are not reported.

Keep per-image notes internal until every image is processed. Do not stream partial reports.

Extract the Figma link (once per article)

If any entry has a non-null article_path, open that markdown file once and grep its YAML frontmatter for a figma: key (the value is a figma.com URL). Remember the value — the report header will surface it so the content developer can jump straight to Figma to fix things. If the frontmatter has no figma: field, or the value is empty, skip the link entirely (don't print an empty Figma: line).

When multiple articles reference different screenshots (branch-diff mode), collect the unique Figma URLs per article and emit them grouped under each article in the header. In the common single-article case, one line is enough.

Step 3: Emit the summary

Follow this exact format:

## Screenshot review: <article filename or "branch changes">

Figma: <url from frontmatter — omit this line entirely when no figma key>

Checked N screenshots. M need changes.

### <image relative path>
- ❌ <short description of the failure — reference the rule>
- ⚠️ <short description of a warning>

### <next image relative path>
- ❌ <...>

Rules:

• If N > 0 and M == 0: replace the body with All N screenshots pass. and skip the per-image sections entirely. Keep the Figma: line in the header if it was extracted.
• Severity: ❌ means "must fix before the article ships"; ⚠️ means "a designer should eyeball this, but it might be acceptable".
• Never list a rule that passed — the point is to be short.
• Don't repeat the rubric text. Quote the rule name only if needed for clarity.

Calibration (one-off)

visual-rules-screenshots.md starts as a placeholder. To populate it:

1. Gather a reference set of approved PNG screenshots from docs-next.
2. Run python3 <skill-dir>/scripts/calibrate.py <path-or-folder> [<path-or-folder> …]. The script walks the paths, prints one image per turn, and expects the assistant to describe what it sees and cluster findings into concrete rules.
3. When done, the script writes a draft visual-rules-screenshots.md. Review and edit it — the skill uses whatever is in that file.
4. Re-run calibration whenever the Figma library changes (new highlight component, new cursor asset, etc.) so the rubric stays current.

If the calibration output looks thin or inconsistent across runs, switch to authoring the rules manually — the skill doesn't care how the file was produced, only that it describes checkable rules.