claude-tap is a local proxy and trace viewer for AI coding agents, recording and displaying their API requests, prompts, tool calls, responses, context, and token usage. It helps developers inspect and compare agent runs from tools such as Claude Code, Codex CLI, Gemini CLI, Cursor CLI, and others, while the catalogue skills and instruction support work with the project.
Borrowing it
Nothing to install: this file belongs to liaohch3/claude-tap. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/liaohch3/claude-tap/main/.agents/skills/screenshot-validation/SKILL.mdgit clone --depth 1 https://github.com/liaohch3/claude-tapWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/liaohch3/claude-tap/screenshot-validation)<a href="https://agentmods.dev/skills/liaohch3/claude-tap/screenshot-validation"><img src="https://agentmods.dev/badge/skills/liaohch3/claude-tap/screenshot-validation/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/liaohch3/claude-tap/screenshot-validation"><img src="https://agentmods.dev/badge/skills/liaohch3/claude-tap/screenshot-validation.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00066 | $0.00656 |
| Opus 5.5 | $0.00026 | $0.00262 |
| Sonnet 5.5 | $0.00013 | $0.00131 |
| Haiku 4.5 | $0.00007 | $0.00066 |
Grade A, and why
screenshot-validation scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 1mo ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 77 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Screenshot Validation
Validate that evidence images and viewer HTML files meet quality standards before committing. This catches issues that would otherwise fail CI or produce misleading PR evidence.
Image quality check
Checks PNG/JPG/GIF/WEBP files for:
- Minimum dimensions: 400x400 pixels (hard fail)
- Desktop viewport width: >= 1280px (warning if narrower)
- File size: <= 5MB (warning if larger)
- Blankness detection (PNG only): fails if > 90% of pixels are white/transparent
Run on specific files or directories
uv run python scripts/check_screenshots.py .agents/evidence/pr/
uv run python scripts/check_screenshots.py .agents/recordings/
uv run python scripts/check_screenshots.py path/to/specific-image.png
Run on git-staged images
scripts/check_screenshots.sh
This shell wrapper automatically finds staged PNG/JPG files and runs the quality check on them — useful as a pre-commit sanity check.
Viewer HTML rendering verification
Uses Playwright (headless Chromium) to verify that generated viewer HTML files actually render correctly — not just raw JSON or Python errors.
Checks:
- No JavaScript errors on page load
- Normal traces render a sidebar with entries and a detail panel
- Empty embedded traces render the explicit "No API calls captured" state
- Body text doesn't contain raw JSON dumps or Python tracebacks
Run
uv run python scripts/verify_screenshots.py .traces/trace_*.html
Requires Playwright to be installed (uv pip install playwright && playwright install chromium).
Typical workflow
After generating new evidence for a PR:
# 1. Check image quality
uv run python scripts/check_screenshots.py .agents/evidence/pr/
# 2. If you generated new viewer HTML, verify it renders
uv run python scripts/verify_screenshots.py .traces/trace_*.html
# 3. If all passes, stage and commit
git add .agents/evidence/pr/
Fixing common failures
| Failure | Fix |
|---|---|
very small image (WxH; minimum is 400x400) |
Retake screenshot at a larger viewport or higher resolution |
narrow desktop viewport (Wpx < 1280px) |
Resize browser window to >= 1280px wide before capturing |
mostly blank/white image |
Ensure the screenshot captures actual content, not an empty page |
No sidebar — viewer not rendered |
Viewer HTML is broken; regenerate from trace JSONL |
JS errors |
Check viewer.html for syntax errors in embedded data |
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 1mo ago First seen · 77 lines · 66 tokens per session scan A 23311cb5e711
screenshot-validation is a skill published in the GitHub repository liaohch3/claude-tap (3,311 stars, last pushed today), licensed MIT. It adds 66 tokens to every session and 656 once invoked, about $0.0003 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
Other skills, from other repositories
browser-use
Direct browser control via CDP for web interaction: automation, scraping, testing, screenshots, and site/app work. Also covers hosted cloud browsers for AI agents: the browser-use Python library (Browser(usecloud=True)), Playwright, Puppeteer or any CDP client.
qa
QA-test a website or web app and return a 1-5 quality score (5 = flawless, 1 = broken) with evidence. Use when the user wants to test, QA, evaluate, score, or "check how good" a site, page, flow, or app — including a local dev server (e.g. "qa test localhost:5173", "does the checkout work?", "rate this landing page").…
implement-rfc
Implement one RFC: check its predecessors, present a plan for approval, write the code, then demonstrate every acceptance criterion.
test-strategy
Write TEST-STRATEGY.md, a test plan per RFC, before the tests are written.
recipe-eval-prompt
Compares original and optimized prompts through repeated blind paired execution in git worktrees. Use when evaluating prompt improvement effects or learning prompt engineering through concrete examples.
prodtest
Senior-QA test pass on a newly implemented feature. Detects the project's real test stack, writes unit and functional/integration tests, then drives the running app with Playwright for end-to-end coverage, saving screenshots to a gitignored folder for human review. Asks upfront whether found bugs should be fixed or…