react18-test-guardian

react18-test-guardian is an agent for Claude Code from jiamaozheng/awesome-claude-code. It costs 81 tokens per session (2,886 once invoked), scanned A, original, no licence file.

A React test migration specialist for moving applications from React 16 or 17 to React 18.3.1.

In plain words
What is it for?
It fixes these test regressions, updates affected counts, rewrites Enzyme tests when needed, and repeats the test run until there are no failures.
Why use it?
React 18 changes how asynchronous updates, automatic batching, and StrictMode affect tests; projects using Enzyme may also need tests rewritten with React Testing Library.

Agent for Claude Code

Written for Claude Code: a Claude Code subagent (agents/*.md). Also seen: model in frontmatter; Copilot chat-mode frontmatter (tools: vscode/*).

Good fit It fixes these test regressions, updates affected counts, rewrites Enzyme tests when needed, and repeats the test run until there are no failures.

Compare 6 agents from other repositories ↓
Install with agentmods
npx agentmods add agents/jiamaozheng/awesome-claude-code/react18-test-guardian
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.

Clone the repo
git clone --depth 1 https://github.com/jiamaozheng/awesome-claude-code

Made for: Claude Code.

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 react18-test-guardian

README.md
[![agentmods](https://agentmods.dev/badge/agents/jiamaozheng/awesome-claude-code/react18-test-guardian.svg)](https://agentmods.dev/agents/jiamaozheng/awesome-claude-code/react18-test-guardian)
Your own site
<a href="https://agentmods.dev/agents/jiamaozheng/awesome-claude-code/react18-test-guardian"><img src="https://agentmods.dev/badge/agents/jiamaozheng/awesome-claude-code/react18-test-guardian.svg" alt="Measured on agentmods" height="20"></a>
Per session 81 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 2,886 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin unknown No closer match found 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 $0.00081 $0.02886
Opus 5 $0.00041 $0.01443
Sonnet 5 $0.00016 $0.00577
Haiku 4.5 $0.00008 $0.00289

Measured 4d ago against content hash 6e9aac7dd3fd, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-08, from the pricing page.

Security

Grade A, and why

react18-test-guardian 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 4d 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.

agents/react18-test-guardian.md · 369 lines

The source is not reproduced here

No licence file

A repository with no LICENSE is all rights reserved by default, so the body is not copied here. The metadata, the measurements and the link are.

Read it on GitHub

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. 4d ago First seen · 369 lines · 81 tokens per session scan A 6e9aac7dd3fd

Subscribe to this mod's changes

react18-test-guardian is an agent published in the GitHub repository jiamaozheng/awesome-claude-code (1 stars, last pushed yesterday), with no licence file. It adds 81 tokens to every session and 2,886 once invoked, about $0.0004 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 2026-09-03.

Related

Other agents, from other repositories

ts-tester

Write concise, resilient, modern Unit, Component, and Hook tests using Vitest and React Testing Library for Next.js project. Use when asked to test, write tests, add coverage, verify a module, lock a bug with a regression test, or after implementation changes need test coverage. Also use when the user mentions Vitest…

sergeyklay/.agents · 127 tokens

frontend-test-engineer

Frontend test engineer for Arthur MCP. Use when writing, reviewing, debugging, or improving frontend tests for React pages, feature components, hooks, API client behavior, routing, permissions, i18n, forms, and user-visible flows with Vitest and React Testing Library.

alexmmatos/arthur-mcp · 59 tokens

test-writer

Writes tests following project conventions — pytest async for backend, Jest + React Testing Library for the web app. Use when you need tests for new or existing code.

aliafsahnoudeh/figma-to-code-claude-pipeline · 36 tokens

react-test-writer

This agent MUST BE USED PROACTIVELY whenever new React/TypeScript components are created, existing ones are modified, or application logic changes require validation through tests. It should not only be triggered when explicitly requested, but also automatically after frontend features, bug fixes, or refactors to…

cicababba/claude-plugins-marketplace · 292 tokens

react19-test-guardian

Test suite fixer and verification specialist. Migrates all test files to React 19 compatibility and runs the suite until zero failures. Uses memory to track per-file fix progress and failure history. Does not stop until npm test reports 0 failures. Invoked as a subagent by react19-commander.

KIMISKI33/awesome-copilot · 67 tokens

react19-dep-surgeon

Dependency upgrade specialist. Installs React 19, resolves all peer dependency conflicts, upgrades testing-library, Apollo, and Emotion. Uses memory to log each upgrade step. Returns GO/NO-GO to the commander. Invoked as a subagent by react19-commander.

archubbuck/workspace-architect · 63 tokens