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 skills/posthog/posthog-foss/react-doctornpx skills add PostHog/posthog-foss --skill react-doctorgit clone --depth 1 https://github.com/PostHog/posthog-fossWrote 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/posthog/posthog-foss/react-doctor)<a href="https://agentmods.dev/skills/posthog/posthog-foss/react-doctor"><img src="https://agentmods.dev/badge/skills/posthog/posthog-foss/react-doctor.svg" alt="Measured on agentmods" 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 | $0.00032 | $0.00346 |
| Opus 5 | $0.00016 | $0.00173 |
| Sonnet 5 | $0.00006 | $0.00069 |
| Haiku 4.5 | $0.00003 | $0.00035 |
Grade A, and why
react-doctor 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 5d 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.
Copies of this mod
1 near-identical copy found in the catalogue:
- react-doctor — 91% identical, 7 lines differ
What it actually says
React Doctor
Scans your React codebase for security, performance, correctness, and architecture issues. Outputs a 0-100 score with actionable diagnostics.
Usage
npx -y react-doctor@latest . --verbose
Workflow
- Run the command above at the project root
- Read every diagnostic with file paths and line numbers
- Fix issues starting with errors (highest severity)
- Re-run to verify the score improved
Rules (47+)
- Security: hardcoded secrets in client bundle, eval()
- State & Effects: derived state in useEffect, missing cleanup, useState from props, cascading setState
- Architecture: components inside components, giant components, inline render functions
- Performance: layout property animations, transition-all, large blur values
- Correctness: array index as key, conditional rendering bugs
- Next.js: missing metadata, client-side fetching for server data, async client components
- Bundle Size: barrel imports, full lodash, moment.js, missing code splitting
- Server: missing auth in server actions, blocking without after()
- Accessibility: missing prefers-reduced-motion
- Dead Code: unused files, exports, types
Score
- 75+: Great
- 50-74: Needs work
- 0-49: Critical
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.
- 5d ago First seen · 42 lines · 32 tokens per session scan A f2b529172abd
react-doctor is a skill published in the GitHub repository PostHog/posthog-foss (712 stars, last pushed today), licensed MIT. It adds 32 tokens to every session and 346 once invoked, about $0.0002 per session on Opus 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.
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