LABSCO SUMMARY
react-native-harness is one skill, teaching an agent to write Jest-style tests that run on a real iOS simulator, Android emulator, or browser, with full access to native modules.
The single skill covers everything the library does: importing from react-native-harness, mocking modules, spying on functions, rendering React Native components on-device, wiring setupFiles and setupFilesAfterEnv, and adding the optional @react-native-harness/ui package for UI-level tests. It fills a specific gap — Jest alone runs in Node and can't touch a real native module, and Maestro drives the UI but has no describe/it test syntax.
This is for a React Native team that wants native-module or platform-specific behavior under real test coverage, not for a project whose tests are pure JavaScript logic that Jest already covers on its own. Running it means having an actual iOS or Android environment configured — a simulator, an emulator, or a real device — or a browser for the web target, not just installing an npm package.
The README documents running react-native-harness in CI/CD as a feature, but there is no second skill covering it — the single skill here is the whole package, and its accuracy is the whole bet if the library's API changes.
WHAT'S INSIDE
A signpost rather than a manual: it checks that your copy of React Native Harness, the on-device test runner, is recent enough, then loads the testing guide that belongs to that exact version so you never follow instructions written for a different one.
INSTALL
REPOSITORY INSTALL
Run this outside your AI tool, using Node.js 22.20.0 or newer. Skills CLI 1.7.2 skips skill selection; prompts cancel installation without an interactive terminal. If choosing Project when asked about installation scope, open your project's folder before running this.
Install checklist
Additional agents. ↑/↓ moves, Space toggles selections, Enter confirms.Installing to: for your intended tool. Stop if it names a different tool.Symlink (Recommended) for shared files or Copy to all agents for separate copies; review the summary before confirming installation.Install the find-skills skill? defaults to Yes, adding another skill for all projects. Choose No if you don't want that extra installation.npx skills add callstackincubator/react-native-harnessSINGLE SKILL
Run this outside your AI tool, using Node.js 22.20.0 or newer. Skills CLI 1.7.2 skips skill selection; prompts cancel installation without an interactive terminal. If choosing Project when asked about installation scope, open your project's folder before running this.
Install checklist
Additional agents. ↑/↓ moves, Space toggles selections, Enter confirms.Installing to: for your intended tool. Stop if it names a different tool.Symlink (Recommended) for shared files or Copy to all agents for separate copies; review the summary before confirming installation.Install the find-skills skill? defaults to Yes, adding another skill for all projects. Choose No if you don't want that extra installation.npx skills add callstackincubator/react-native-harness --skill "react-native-harness" --full-depth