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 skills add existential-birds/beagle --skill review-frontendgit clone --depth 1 https://github.com/existential-birds/beagleWrote 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/existential-birds/beagle/review-frontend)<a href="https://agentmods.dev/skills/existential-birds/beagle/review-frontend"><img src="https://agentmods.dev/badge/skills/existential-birds/beagle/review-frontend/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/existential-birds/beagle/review-frontend"><img src="https://agentmods.dev/badge/skills/existential-birds/beagle/review-frontend.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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 | $0.00033 | $0.02289 |
| Opus 5.5 | $0.00013 | $0.00916 |
| Sonnet 5.5 | $0.00007 | $0.00458 |
| Haiku 4.5 | $0.00003 | $0.00229 |
Grade A, and why
review-frontend 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 — 218 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Frontend Code Review
Arguments
--parallel: Hint to fan out per technology area when the agent supports subagents (see Step 5). When unsupported, the review runs sequentially with identical output.- Path: Target directory (default: current working directory)
Step 1: Identify Changed Files
git diff --name-only $(git merge-base HEAD main)..HEAD | grep -E '\.(tsx?|jsx?|mjs|cjs|css)$|^(remix|vite)\.config\.'
Step 2: Detect Technologies
# Detect Remix v2 (any official adapter). When matched, the Remix-specific
# surface is delegated to the review-remix-v2 skill in Step 4.
grep -E '"@remix-run/(react|node|cloudflare|deno|serve)"' package.json | head -3
# Detect React Flow
grep -r "@xyflow/react\|ReactFlow\|useNodesState" --include="*.tsx" -l | head -3
# Detect Zustand
grep -r "from 'zustand'\|create\(\(" --include="*.ts" --include="*.tsx" -l | head -3
# Detect Tailwind v4
grep -r "@theme\|@layer theme" --include="*.css" -l | head -3
# Check for test files
git diff --name-only $(git merge-base HEAD main)..HEAD | grep -E '\.test\.tsx?$'
Step 3: Load Verification Protocol
Load the review-verification-protocol skill before any substantive judgment on code.
Pass before Step 5: The skill is loaded (or its checklist is open in context). Do not classify severity or write findings until this gate clears.
Step 4: Load Skills
Read each applicable skill below (open its SKILL.md) so its guidance is in context before you review that area.
Remix v2 branch (Step 2 detected @remix-run/* in package.json):
- Load review-remix-v2 — umbrella orchestrator that loads all six Remix v2 area review skills (routing, data-flow, forms, error-boundaries, perf/SSR, meta+sessions) with its own detection telemetry. Run it for the Remix-specific surface and consolidate its findings into this review's output.
- Do NOT also load react-router-code-review — Remix v2 sits on React Router v6 but routes through Remix's route module conventions, which remix-v2-routing-review (loaded via the umbrella) covers in that context.
- Still load shadcn-code-review and the conditional skills below — they're orthogonal to the Remix layer and apply to component/styling/state code regardless of router.
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 · 218 lines · 33 tokens per session scan A 60533bb0fabc
review-frontend is a skill published in the GitHub repository existential-birds/beagle (82 stars, last pushed 1mo ago), licensed Apache-2.0. It adds 33 tokens to every session and 2,289 once invoked, about $0.0001 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 2026-09-16.
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