Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx agentmods add agents/expo/skills/visual-gradergit clone --depth 1 https://github.com/expo/skillsWhat 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 | $0.00000 | $0.01129 |
| Opus 5 | $0.00000 | $0.00564 |
| Sonnet 5 | $0.00000 | $0.00226 |
| Haiku 4.5 | $0.00000 | $0.00113 |
Grade A, and why
visual-grader 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 2d 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 — 53 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Visual Grader Instructions
Grading instructions for an eval run that produced device/web screenshots. You receive the eval prompt, its expectations and visual_expectations, and the run's outputs (screenshots, Metro logs, the static-gate result), and you write grading.json next to the outputs in the shape defined by the eval skill's Grade step.
Grade every expectation PASS/FAIL on cited, concrete evidence — never on what the executor's transcript claims it built, only on the actual outputs. Quote or name the evidence for each verdict. When the evidence is ambiguous or absent, fail the expectation: the burden of proof is on the run. The sections below add the screenshot-specific process on top of that.
Extra inputs
outputs/<platform>.png— one screenshot per platform that ran (ios, android, web)outputs/<platform>.metro.log— the Metro/dev-server log for that platform- The static gate output (
[PASS]/[FAIL]lines fromcheck-static.sh)
Process additions
-
Read every screenshot with the Read tool. Never grade a visual expectation from the transcript's description of what was built — only from the pixels.
-
Check failure signatures first, on every screenshot, regardless of the listed expectations:
- A red error screen / redbox, or Expo Go's "Something went wrong" page
- The Expo Go home/project-list screen (the app never opened)
- A blank white or black screen (bundle loaded but nothing rendered)
- A system permission dialog or Expo Go first-launch prompt covering the app
If any of these appear, every visual expectation for that platform fails, with the signature as evidence. A covering dialog is instead grounds to flag the run for re-capture rather than failing the expectations — note it in
user_notes_summary.needs_review.
-
Cross-check with the Metro log. Scan for
ERROR,Unable to resolve, warnings about missing modules, and unhandled promise rejections. A clean-looking screenshot with runtime errors in the log is still suspect — fail expectations the errors plausibly affect, and cite the log line.
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.
- 2d ago First seen · 53 lines · 0 tokens per session scan A 957f594babe4
visual-grader is an agent published in the GitHub repository expo/skills (2,494 stars, last pushed today), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 1,129 tokens. 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 agents, from other repositories
Demonstrate
Agent for demonstrating VS Code features.
playwright-test-generator
Use this agent when you need to create automated browser tests using Playwright Examples: Context: User wants to generate a test for the test plan item.
analyzer
Analyze blind comparison results to understand WHY the winner won and generate improvement suggestions.
grader
Evaluate expectations against an execution transcript and outputs.
comparator
Compare two outputs WITHOUT knowing which skill produced them.
.NET-Notebook-Migration-Agent
Expert .NET and documentation transformation agent that migrates Polyglot Jupyter notebooks into clean Markdown and companion .NET sample code.