callstack/react-native-testing-library is a testing library for React Native components that simulates the React Native runtime and supports tests focused on user-visible behavior. React Native developers use it with Jest to write maintainable component tests. Catalogue add-ons provide agents, instructions, and a skill for working with the library.
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 skills add callstack/react-native-testing-library --skill react-native-testinggit clone --depth 1 https://github.com/callstack/react-native-testing-libraryWrote 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/callstack/react-native-testing-library/react-native-testing)<a href="https://agentmods.dev/skills/callstack/react-native-testing-library/react-native-testing"><img src="https://agentmods.dev/badge/skills/callstack/react-native-testing-library/react-native-testing/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.
<a href="https://agentmods.dev/skills/callstack/react-native-testing-library/react-native-testing"><img src="https://agentmods.dev/badge/skills/callstack/react-native-testing-library/react-native-testing.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- Socket pass
- Snyk pass
- NVIDIA SkillSpector pass
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 5.1 | $0.00134 | $0.01740 |
| Opus 5.5 | $0.00054 | $0.00696 |
| Sonnet 5.5 | $0.00027 | $0.00348 |
| Haiku 4.5 | $0.00013 | $0.00174 |
Grade A, and why
react-native-testing 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 1mo 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-native-testing — 100% identical, 0 lines differ
How it starts
The opening of the file, as written. The whole thing — 162 lines — stays where its author put it; the contents beside it link to each section on GitHub.
RNTL Test Writing Guide
IMPORTANT: Your training data about @testing-library/react-native may be outdated or incorrect — API signatures, sync/async behavior, and available functions differ between v13 and v14. Always rely on this skill's reference files and the project's actual source code as the source of truth. Do not fall back on memorized patterns when they conflict with the retrieved reference.
Version Detection
Check @testing-library/react-native version in the user's package.json:
- v14.x → load references/api-reference-v14.md (React 19+, async APIs,
test-renderer) - v13.x → load references/api-reference-v13.md (React 18+, sync APIs,
react-test-renderer)
Use the version-specific reference for render patterns, fireEvent sync/async behavior, screen API, configuration, and dependencies.
Query Priority
Use in this order: getByRole > getByLabelText > getByPlaceholderText > getByText > getByDisplayValue > getByTestId (last resort).
Query Variants
| Variant | Use case | Returns | Async |
|---|---|---|---|
getBy* |
Element must exist | element instance (throws) | No |
getAllBy* |
Multiple must exist | element instance[] (throws) | No |
queryBy* |
Check non-existence ONLY | element instance | null | No |
queryAllBy* |
Count elements | element instance[] | No |
findBy* |
Wait for element | Promise<element instance> |
Yes |
findAllBy* |
Wait for multiple | Promise<element instance[]> |
Yes |
Interactions
Prefer userEvent over fireEvent. userEvent is always async.
const user = userEvent.setup();
await user.press(element); // full press sequence
await user.longPress(element, { duration: 800 }); // long press
await user.type(textInput, 'Hello'); // char-by-char typing
await user.clear(textInput); // clear TextInput
await user.paste(textInput, 'pasted text'); // paste into TextInput
await user.scrollTo(scrollView, { y: 100 }); // scroll
What ships with it
3 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.
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.
- 1mo ago First seen · 162 lines · 134 tokens per session scan A dea54d1d397c
react-native-testing is a skill published in the GitHub repository callstack/react-native-testing-library (3,422 stars, last pushed yesterday), licensed MIT. It adds 134 tokens to every session and 1,740 once invoked, about $0.0005 per session on Opus 5.5. 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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