react-testing-library

react-testing-library is a skill for Claude Code, Codex from pproenca/dot-skills. It costs 55 tokens per session (1,589 once invoked), scanned A, original, MIT.

A guide to writing React Testing Library tests that check components through the way users interact with them. React Testing Library is a tool for testing React interfaces without depending heavily on their internal implementation.

In plain words
What is it for?
Use it to write or review component tests, choose queries, handle asynchronous updates, simulate interactions, and check accessibility.
Why use it?
It helps avoid brittle tests that pass because of internal details but fail to reflect real user behavior.

Skill for Claude CodeCodex

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.

agentmods
npx agentmods add skills/pproenca/dot-skills/react-testing-library
Any agent
npx skills add pproenca/dot-skills --skill react-testing-library
Clone the repo
git clone --depth 1 https://github.com/pproenca/dot-skills

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-testing-library

README.md
[![agentmods](https://agentmods.dev/badge/skills/pproenca/dot-skills/react-testing-library.svg)](https://agentmods.dev/skills/pproenca/dot-skills/react-testing-library)
Your own site
<a href="https://agentmods.dev/skills/pproenca/dot-skills/react-testing-library"><img src="https://agentmods.dev/badge/skills/pproenca/dot-skills/react-testing-library.svg" alt="Measured on agentmods" height="20"></a>
Per session 55 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,589 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original 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 $0.00055 $0.01589
Opus 5 $0.00028 $0.00794
Sonnet 5 $0.00011 $0.00318
Haiku 4.5 $0.00006 $0.00159

Measured yesterday against content hash ed43a296b516, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

react-testing-library 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 yesterday.

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.

skills/.experimental/react-testing-library/SKILL.md · 119 lines

How it starts

The opening of the file, as written. The whole thing — 119 lines — stays where its author put it; the contents beside it link to each section on GitHub.

React Testing Library Best Practices

Comprehensive testing guide for React components using Testing Library, designed for AI agents and LLMs. Contains 43 rules across 9 categories, prioritized by impact to guide test writing and code review.

When to Apply

Reference these guidelines when:

  • Writing new component tests with React Testing Library
  • Selecting queries (getByRole, getByLabelText, etc.)
  • Handling async operations in tests (findBy, waitFor)
  • Simulating user interactions (userEvent)
  • Reviewing tests for anti-patterns and implementation detail testing

Rule Categories by Priority

Priority Category Impact Prefix
1 Query Selection CRITICAL query-
2 Async Handling CRITICAL async-
3 Common Anti-Patterns CRITICAL anti-
4 User Interaction HIGH user-
5 Assertions HIGH assert-
6 Component Setup MEDIUM setup-
7 Test Structure MEDIUM struct-
8 Debugging LOW-MEDIUM debug-
9 Accessibility Testing LOW a11y-

Quick Reference

1. Query Selection (CRITICAL)

2. Async Handling (CRITICAL)

Read the full file on GitHub · 119 lines

Files

What ships with it

47 files 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. yesterday First seen · 119 lines · 55 tokens per session scan A ed43a296b516

Subscribe to this mod's changes

react-testing-library is a skill published in the GitHub repository pproenca/dot-skills (201 stars, last pushed 20d ago), licensed MIT. It adds 55 tokens to every session and 1,589 once invoked, about $0.0003 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.

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