react19-test-guardian

react19-test-guardian is an agent for Claude Code from asleekgeek/claude-multiagent-catalogue. It costs 67 tokens per session (1,877 once invoked), scanned B, original, no licence file.

A test-file migration and verification agent for React 19 projects. It updates tests for React 19 compatibility and reruns them until the test command has no failures.

In plain words
What is it for?
Use it to update React tests, handle migration-related test regressions, and confirm the suite passes.
Why use it?
It addresses test failures caused by changes in React 19 and keeps track of fixes already made. This helps verify that the migration has not left the test suite broken.

Agent for Claude Code

Written for Claude Code: a Claude Code subagent (agents/*.md). Also seen: model in frontmatter.

Good fit Use it to update React tests, handle migration-related test regressions, and confirm the suite passes.

Compare 6 agents from other repositories ↓
Install with agentmods
npx agentmods add agents/asleekgeek/claude-multiagent-catalogue/react19-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/asleekgeek/claude-multiagent-catalogue

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 react19-test-guardian

README.md
[![agentmods](https://agentmods.dev/badge/agents/asleekgeek/claude-multiagent-catalogue/react19-test-guardian/github.svg)](https://agentmods.dev/agents/asleekgeek/claude-multiagent-catalogue/react19-test-guardian)
Your own site
<a href="https://agentmods.dev/agents/asleekgeek/claude-multiagent-catalogue/react19-test-guardian"><img src="https://agentmods.dev/badge/agents/asleekgeek/claude-multiagent-catalogue/react19-test-guardian/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 react19-test-guardian

Your own site · 80×15
<a href="https://agentmods.dev/agents/asleekgeek/claude-multiagent-catalogue/react19-test-guardian"><img src="https://agentmods.dev/badge/agents/asleekgeek/claude-multiagent-catalogue/react19-test-guardian.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 67 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 1,877 The whole file, excluding the scripts and references it only reads on demand.
Security scan B 1 finding. 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 $0.00067 $0.01877
Opus 5 $0.00034 $0.00938
Sonnet 5 $0.00013 $0.00375
Haiku 4.5 $0.00007 $0.00188

Measured 9d ago against content hash d54fd66600f3, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-12, from the pricing page.

Security

Grade B, and why

react19-test-guardian scanned grade B 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.

Unrestricted tool accessmediumExcessive agency

A wildcard tool grant or "run any command" leaves no least-privilege boundary at all.

- #tool:* prefix stripped
agents/react19-test-guardian.md · 257 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. 9d ago First seen · 257 lines · 67 tokens per session scan B d54fd66600f3

Subscribe to this mod's changes

react19-test-guardian is an agent published in the GitHub repository asleekgeek/claude-multiagent-catalogue (2 stars, last pushed 3mo ago), with no licence file. It adds 67 tokens to every session and 1,877 once invoked, about $0.0003 per session on Opus 5. A static security scan graded it B with 1 finding (unrestricted tool access). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-03.

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