feature-flags
- Repo stars 245,422
- Author updated Live
- Author repo react
- Domain
- AI
- Compatible agents
-
- Claude Code
- Cursor
- Cline
- Codex
- Windsurf
- Gemini CLI
- +20
- Trust score
- 88 / 100 · community maintained
- Author / version / license
- @facebook · no license declared
- Token usage
- Lean
- Setup complexity
- Plug-and-play
- External API key
- Not required
- Operating systems
- Unspecified (assume cross-platform)
- Runtime requirements
- No special requirements
- Permissions
-
- Read-only
- Write / modify
- Network behavior
- Local-only
- Install commands
- 26 variants
Profile is derived at build time from SKILL.md and install vectors. Subject to drift from author intent.
Heads up: 未限定 allowed-tools，默认拥有全部工具权限。
---
name: feature-flags
description: Use when feature flag tests fail, flags need updating, understanding @gate pragmas, debugging ch…
category: ai
runtime: no special runtime
---
# feature-flags output preview
## PART A: Task fit
- Use case: Use when feature flag tests fail, flags need updating, understanding @gate pragmas, debugging channel-specific test failures, or adding new flags to React. | File | Purpose | |------|---------| | packages/shared/ReactFeatureFlags.js | Default flags (canary), EXPERIMENTAL overrides | runs entirely locally. Works with Claude Code, Cursor, Cline and 23 more..
- Inputs: target material, constraints, expected output, and acceptance criteria.
- Evidence boundary: follow “Flag Files / Gating Tests / @gate pragma (test-level)” and do not present inference as author intent.
## PART B: Execution result
- **01** The card summarizes the use case; runtime output centers on “Use when feature flag tests fail, flags need updating, understanding @gate pragmas, debugging channel-specific test failures, or adding new flags to React. | File | Purpose | |------|---------| | packages/shared/ReactFeatureFlags.js | Default flags (canary), EXPERIMENTAL overrides | runs entirely locally. Works with Claude Code, Cursor, Cline and 23 more.”.
- **02** When the source has headings, the agent prioritizes “Flag Files / Gating Tests / @gate pragma (test-level)” so the result follows the author’s structure.
- **03** Typical output includes task judgment, concrete steps, required commands or file edits, validation, and follow-up options.
- **04** Risk context follows the fingerprint: read files, write/modify files; mostly runs locally; usually needs no extra API key.
## Running Rules
- read files, write/modify files; mostly runs locally; usually needs no extra API key.
- Validate with a small sample before expanding scope.
- Return the result, validation criteria, and next iteration options. Choose the trigger
The source mentions slash commands such as `/flags`, `/test`; use them first when your agent supports command triggers.
Provide inputs and boundaries
Name target files or source material, expected output, forbidden changes, and whether network or shell access is allowed. Permission fingerprint: read files, write/modify files.
Validate with a small run
Start with a small task and check whether the result follows “Flag Files / Gating Tests / @gate pragma (test-level)”. Inspect diffs, logs, previews, or tests before expanding scope.
Review before delivery
Confirm the final output includes a concrete result, evidence, and next action. If it stays generic, tighten inputs, boundaries, and acceptance criteria.
---
name: feature-flags
description: Use when feature flag tests fail, flags need updating, understanding @gate pragmas, debugging ch…
category: ai
source: facebook/react
---
# feature-flags
## When to use
- Use when feature flag tests fail, flags need updating, understanding @gate pragmas, debugging channel-specific test fa…
- Use it when the task has clear inputs, repeatable steps, and validation criteria.
## What to provide
- Target material, scope, expected result, and forbidden changes.
- Whether network, commands, file writes, or external services are allowed.
## Execution rules
- Organize steps around “Flag Files / Gating Tests / @gate pragma (test-level)” and keep inference separate from source facts.
- read files, write/modify files; mostly runs locally; usually needs no extra API key.
- Validate with a small sample before expanding the task.
## Output requirements
- Return the deliverable, key evidence, validation method, and next action.
- Mark missing information as unknown; do not invent commands, platforms, or dependencies. Evidence boundary and execution chain
The author source anchors workflow facts; repository files anchor sources and commands; Fluxly only adds fit, limitations, and quality judgment.
skill "feature-flags" {
input -> user goal + target files + boundaries + acceptance criteria
context -> Flag Files / Gating Tests / @gate pragma (test-level)
rules -> SKILL.md triggers / order / output contract
runtime -> no special runtime | read files, write/modify files | mostly runs locally
guardrails -> usually needs no extra API key + small-sample validation + diff/log review
output -> copyable result + checklist + next iteration
}React Feature Flags
Flag Files
| File | Purpose |
|---|---|
packages/shared/ReactFeatureFlags.js |
Default flags (canary), __EXPERIMENTAL__ overrides |
packages/shared/forks/ReactFeatureFlags.www.js |
www channel, __VARIANT__ overrides |
packages/shared/forks/ReactFeatureFlags.native-fb.js |
React Native, __VARIANT__ overrides |
packages/shared/forks/ReactFeatureFlags.test-renderer.js |
Test renderer |
Gating Tests
@gate pragma (test-level)
Use when the feature is completely unavailable without the flag:
// @gate enableViewTransition
it('supports view transitions', () => {
// This test only runs when enableViewTransition is true
// and is SKIPPED (not failed) when false
});gate() inline (assertion-level)
Use when the feature exists but behavior differs based on flag:
it('renders component', async () => {
await act(() => root.render(<App />));
if (gate(flags => flags.enableNewBehavior)) {
expect(container.textContent).toBe('new output');
} else {
expect(container.textContent).toBe('legacy output');
}
});Adding a New Flag
- Add to
ReactFeatureFlags.jswith default value - Add to each fork file (
*.www.js,*.native-fb.js, etc.) - If it should vary in www/RN, set to
__VARIANT__in the fork file - Gate tests with
@gate flagNameor inlinegate()
Checking Flag States
Use /flags to view states across channels. See the flags skill for full command options.
__VARIANT__ Flags (GKs)
Flags set to __VARIANT__ simulate gatekeepers - tested twice (true and false):
/test www <pattern> # __VARIANT__ = true
/test www variant false <pattern> # __VARIANT__ = falseDebugging Channel-Specific Failures
- Run
/flags --diff <channel1> <channel2>to compare values - Check
@gateconditions - test may be gated to specific channels - Run
/test <channel> <pattern>to isolate the failure - Verify flag exists in all fork files if newly added
Common Mistakes
- Forgetting both variants - Always test
wwwANDwww variant falsefor__VARIANT__flags - Using @gate for behavior differences - Use inline
gate()if both paths should run - Missing fork files - New flags must be added to ALL fork files, not just the main one
- Wrong gate syntax - It's
gate(flags => flags.name), notgate('name')
Decide Fit First
Design Intent
How To Use It
Boundaries And Review