React Native Harness Agent Skill
Write and debug React Native Harness tests for app code. Use when the user asks to create or fix tests that import from react-native-harness, mock modules, spy on functions, render React Native components on-device, use setupFiles or setupFilesAfterEnv, or add optional UI tests with @react-native-harness/ui.
Install
one command, takes just this skill from the repositorynpx skills add https://github.com/callstackincubator/react-native-harness --skill react-native-harnessWhat comes with it
2 858 bytes besides the instructionThe instruction itself
as written by the authorRouter only. Private setup before using this skill:
harness --version
Require react-native-harness >= 1.3.0-rc.1; older CLIs lack these skill commands. If older, run npm install -g react-native-harness@latest, recheck, then continue. If you cannot upgrade, stop and tell the user. Do not include version or upgrade commands in final plans.
Before your first Harness command or plan, read the version-matched CLI guide:
harness skill get core
If you need more details on Harness, see the available CLI skill guides:
harness skill list
Load additional skills via harness skill get <name> when needed.
Use this skill only to route into version-matched CLI guidance. Let the installed CLI skill files provide exact workflow guidance, API usage, and current test-writing rules.
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How to use it
Take callstackincubator/react-native-harness from the repository into ~/.claude/skills for personal
use, or into .claude/skills inside a project.
The agent identifies a skill by the name field in its header. Two skills with the
same name cannot sit side by side — one of them will be ignored.
The instructions reference npm.
Without those the skill loads but fails at the first command.