react-doctor

react-doctor is a skill for Claude Code, Codex from JustineDevs/premortem. It costs 70 tokens per session (626 once invoked), scanned A, a copy of react-doctor, Apache-2.0.

A diagnostic checklist for React code that scans for security, performance, correctness, accessibility, bundle-size, and architecture problems. It also checks whether recent changes caused the project's health score to drop.

In plain words
What is it for?
Use it after changing React code, when fixing a bug, or when you want a full cleanup and triage pass on a React project.
Why use it?
It helps find problems before they reach users or get committed. The scan groups findings by severity so you can address the most serious issues first.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one. Also seen: installed under .agents/ (shared by several agents).

Good fit Use it after changing React code, when fixing a bug, or when you want a full cleanup and triage pass on a React project.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/justinedevs/premortem/react-doctor
Install

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.

Any agent
npx skills add JustineDevs/premortem --skill react-doctor
Clone the repo
git clone --depth 1 https://github.com/JustineDevs/premortem

Made for: Claude Code, Codex.

Wrote 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.

agentmods badge for react-doctor

README.md
[![agentmods](https://agentmods.dev/badge/skills/justinedevs/premortem/react-doctor/github.svg)](https://agentmods.dev/skills/justinedevs/premortem/react-doctor)
Your own site
<a href="https://agentmods.dev/skills/justinedevs/premortem/react-doctor"><img src="https://agentmods.dev/badge/skills/justinedevs/premortem/react-doctor/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.

agentmods 80×15 button for react-doctor

Your own site · 80×15
<a href="https://agentmods.dev/skills/justinedevs/premortem/react-doctor"><img src="https://agentmods.dev/badge/skills/justinedevs/premortem/react-doctor.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 70 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 626 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 1 finding. A grade says what 26 rules found in the file — not that it is safe.
Origin 83% copy Near-identical to another mod in the catalogue.
Token cost

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.

ModelPer sessionOnce invoked
Fable 5.1 $0.00070 $0.00626
Opus 5 $0.00035 $0.00313
Sonnet 5 $0.00014 $0.00125
Haiku 4.5 $0.00007 $0.00063

Measured 9d ago against content hash df58b3490543, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-12, from the pricing page.

Security

Grade A, and why

react-doctor scanned grade A with 1 finding 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 9d 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.

Makes network callslowCapability

Not a fault in itself. Listed so you know the mod talks to something, and to what.

curl --fail --silent --show-error \
Origin

This is a copy

83% identical to react-doctor — 25 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

.agents/skills/react-doctor/SKILL.md · 52 lines

How it starts

The opening of the file, as written. The whole thing — 52 lines — stays where its author put it; the contents beside it link to each section on GitHub.

React Doctor

Scans React codebases for security, performance, correctness, and architecture issues. Outputs a 0–100 health score.

After making React code changes:

Run npx react-doctor@latest --verbose --scope changed and check the score did not regress.

If the score dropped, fix the regressions before committing.

For general cleanup or code improvement:

Run npx react-doctor@latest --verbose (the default --scope full) to scan the full codebase. Fix issues by severity — errors first, then warnings.

/doctor — full local triage workflow

When the user types /doctor, says "run react doctor", or asks for a full triage / cleanup pass (not just a regression check), fetch the canonical local-triage playbook and follow every step in it:

curl --fail --silent --show-error \
  --header 'Cache-Control: no-cache' \
  https://www.react.doctor/prompts/react-doctor-agent.md

The playbook is the single source of truth — a scan → filter → triage → fix → validate loop that edits the working tree directly (never commits, never opens PRs). Updating the prompt at its source updates every agent on its next fetch — no skill reinstall needed.

Pair it with the matching per-rule prompts at https://www.react.doctor/prompts/rules/<plugin>/<rule>.md (fetched on demand inside the playbook) so each fix uses the canonical, reviewer-tested recipe.

Configuring or explaining rules

When the user wants to understand a rule, disagrees with one, or wants to disable / tune which rules run (not fix code), read references/explain.md and follow it. Start with npx react-doctor@latest rules explain <rule>, then apply the narrowest control via npx react-doctor@latest rules disable|set|category|ignore-tag …, which edits your doctor.config.* (or package.json#reactDoctor).

Command

npx react-doctor@latest --verbose --scope changed
Flag Purpose
. Scan current directory
--verbose Show affected files and line numbers per rule
--scope changed Only report issues introduced vs the base branch (default: full)
--scope lines Only report issues on the changed lines
--score Output only the numeric score

Read the full file on GitHub · 52 lines

Files

What ships with it

1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

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.

  1. 9d ago First seen · 52 lines · 70 tokens per session scan A df58b3490543

Subscribe to this mod's changes

react-doctor is a skill published in the GitHub repository JustineDevs/premortem (2 stars, last pushed 1mo ago), licensed Apache-2.0. It adds 70 tokens to every session and 626 once invoked, about $0.0003 per session on Opus 5. A static security scan graded it A with 1 finding (makes network calls). It is 83% identical to react-doctor, differing in 25 lines, and is treated as a copy.

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