Agent skill

Define Feature Flag

Define a frontend feature flag with defineFlag and wire its readers.

AGPL-3.0Auto-check passedFrontend & Design

Install Define Feature Flag

skills CLI

$ npx skills add macro-inc/macro --skill define-feature-flag -a claude-code

Project install by default; add -g for ~/.claude/skills/.

GitHub CLI

$ gh skill install macro-inc/macro define-feature-flag --agent claude-code

Project scope by default; add --scope user for a personal install. Needs GitHub CLI 2.90.0 or later (public preview).

Manual copy

$ git clone --depth 1 https://github.com/macro-inc/macro.git skills-src && mkdir -p .claude/skills && cp -r skills-src/.claude/skills/define-feature-flag .claude/skills/define-feature-flag && rm -rf skills-src

Use ~/.claude/skills/ instead of .claude/skills for a personal install. The folder must contain SKILL.md.

Claude Code skills documentation · loads skills from .claude/skills/

Paste into Claude Code

Install the "define-feature-flag" agent skill from https://github.com/macro-inc/macro/tree/main/.claude/skills/define-feature-flag into .claude/skills/define-feature-flag/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "define-feature-flag", then confirm the skill loads.

Claude Code copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

$skill-installer

$skill-installer install https://github.com/macro-inc/macro/tree/main/.claude/skills/define-feature-flag

Type this inside Codex. $skill-installer <name> installs a curated skill from openai/skills. The installer writes to $CODEX_HOME/skills (default ~/.codex/skills). Restart Codex if the skill does not show up.

skills CLI

$ npx skills add macro-inc/macro --skill define-feature-flag -a codex

Project install goes to .agents/skills/; add -g for ~/.codex/skills/.

GitHub CLI

$ gh skill install macro-inc/macro define-feature-flag --agent codex

Project scope by default (.agents/skills/); add --scope user for a personal install.

Manual copy

$ git clone --depth 1 https://github.com/macro-inc/macro.git skills-src && mkdir -p .agents/skills && cp -r skills-src/.claude/skills/define-feature-flag .agents/skills/define-feature-flag && rm -rf skills-src

Use ~/.agents/skills/ instead of .agents/skills for a personal install.

Codex skills documentation · loads skills from .agents/skills/

Paste into Codex

Install the "define-feature-flag" agent skill from https://github.com/macro-inc/macro/tree/main/.claude/skills/define-feature-flag into .agents/skills/define-feature-flag/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "define-feature-flag", then confirm the skill loads.

Codex copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

skills CLI

$ npx skills add macro-inc/macro --skill define-feature-flag -a cursor

Project install goes to .agents/skills/; add -g for ~/.cursor/skills/.

GitHub CLI

$ gh skill install macro-inc/macro define-feature-flag --agent cursor

Project scope by default (.agents/skills/); add --scope user for a personal install.

Manual copy

$ git clone --depth 1 https://github.com/macro-inc/macro.git skills-src && mkdir -p .cursor/skills && cp -r skills-src/.claude/skills/define-feature-flag .cursor/skills/define-feature-flag && rm -rf skills-src

Use ~/.cursor/skills/ instead of .cursor/skills for a personal install.

Cursor skills documentation · loads skills from .cursor/skills/, .agents/skills/, .claude/skills/, .codex/skills/

Paste into Cursor

Install the "define-feature-flag" agent skill from https://github.com/macro-inc/macro/tree/main/.claude/skills/define-feature-flag into .cursor/skills/define-feature-flag/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "define-feature-flag", then confirm the skill loads.

Cursor copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

gemini skills install

$ gemini skills install https://github.com/macro-inc/macro.git --path .claude/skills/define-feature-flag

--scope user (default) or --scope workspace; --path is the subfolder of the repo that holds the skill; --consent skips the security confirmation prompt.

skills CLI

$ npx skills add macro-inc/macro --skill define-feature-flag -a gemini-cli

Project install goes to .agents/skills/; add -g for ~/.gemini/skills/.

GitHub CLI

$ gh skill install macro-inc/macro define-feature-flag --agent gemini-cli

Project scope by default (.agents/skills/); add --scope user for a personal install.

Manual copy

$ git clone --depth 1 https://github.com/macro-inc/macro.git skills-src && mkdir -p .gemini/skills && cp -r skills-src/.claude/skills/define-feature-flag .gemini/skills/define-feature-flag && rm -rf skills-src

Use ~/.gemini/skills/ instead of .gemini/skills for a personal install, then run /skills reload.

Gemini CLI skills documentation · loads skills from .gemini/skills/, .agents/skills/

Paste into Gemini CLI

Install the "define-feature-flag" agent skill from https://github.com/macro-inc/macro/tree/main/.claude/skills/define-feature-flag into .gemini/skills/define-feature-flag/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "define-feature-flag", then confirm the skill loads.

Gemini CLI copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

GitHub CLI

$ gh skill install macro-inc/macro define-feature-flag

Installs for Copilot at project scope by default; add --scope user for a personal install. Preview a skill first with gh skill preview. Needs GitHub CLI 2.90.0 or later (public preview).

skills CLI

$ npx skills add macro-inc/macro --skill define-feature-flag -a github-copilot

Project install goes to .agents/skills/; add -g for ~/.copilot/skills/.

Manual copy

$ git clone --depth 1 https://github.com/macro-inc/macro.git skills-src && mkdir -p .github/skills && cp -r skills-src/.claude/skills/define-feature-flag .github/skills/define-feature-flag && rm -rf skills-src

Use ~/.copilot/skills/ instead of .github/skills for a personal install. Commit .github/skills so cloud agent and code review can use it.

GitHub Copilot skills documentation · loads skills from .github/skills/, .claude/skills/, .agents/skills/

Paste into GitHub Copilot

Install the "define-feature-flag" agent skill from https://github.com/macro-inc/macro/tree/main/.claude/skills/define-feature-flag into .github/skills/define-feature-flag/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "define-feature-flag", then confirm the skill loads.

GitHub Copilot copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

skills CLI

$ npx skills add macro-inc/macro --skill define-feature-flag -a opencode

OpenCode documents no install command of its own. Project install goes to .agents/skills/; add -g for ~/.config/opencode/skills/.

GitHub CLI

$ gh skill install macro-inc/macro define-feature-flag --agent opencode

Project scope by default (.agents/skills/); add --scope user for a personal install.

Manual copy

$ git clone --depth 1 https://github.com/macro-inc/macro.git skills-src && mkdir -p .opencode/skills && cp -r skills-src/.claude/skills/define-feature-flag .opencode/skills/define-feature-flag && rm -rf skills-src

Use ~/.config/opencode/skills/ instead of .opencode/skills for a personal install.

OpenCode skills documentation · loads skills from .opencode/skills/, .claude/skills/, .agents/skills/

Paste into OpenCode

Install the "define-feature-flag" agent skill from https://github.com/macro-inc/macro/tree/main/.claude/skills/define-feature-flag into .opencode/skills/define-feature-flag/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "define-feature-flag", then confirm the skill loads.

OpenCode copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

Facts

Skill name: define-feature-flag
GitHub stars: 4.6k
Token cost: ~780 tokens
SKILL.md length: 321 words
Files: 1
Skills in repo: 19
Repo updated: Oct 7, 2026
First seen: Oct 7, 2026
Licence: AGPL-3.0

At a glance

Define a frontend feature flag with defineFlag and wire its readers.

Works in 3 steps: Remote or env-only? → Define it → Read it
Changing a feature flag
SKILL.md covers 1. Remote or env-only?, 2. Define it, 3. Read it and Don't
Instructions only: no scripts, shell commands, URLs or credentials in SKILL.md

What it does

Define Feature Flag is an agent skill from macro-inc/macro. Define a frontend feature flag with defineFlag and wire its readers. Use when adding, suggesting, or changing a feature flag, PostHog flag, ENABLE env flag, useFeatureFlag, isFeatureEnabled, or ShowFeatureFlag.

Its SKILL.md is about 780 tokens, which your agent loads only when the skill is triggered. It is a single SKILL.md file with no bundled scripts.

It sits in Frontend & Design. It works with PostHog. The repository describes itself as: Macro is a unified workspace for teams: email, chat, docs, tasks, agents, calls, and CRM — @-linked together with shared AI memory. The licence is AGPL-3.0.

When your agent uses it

Changing a feature flag
ENABLE env flag
IsFeatureEnabled
ShowFeatureFlag

Example prompts

“/define-feature-flag”

Workflow steps

3 steps, taken from the step headings in SKILL.md.

Remote or env-only?
Define it
Read it

What it can do on your machine

Read from SKILL.md and the folder at commit 39f3c91. It shows what the files ask for, not the result of running them.

Tool permissions
Pre-approves nothing: there is no allowed-tools line, so your agent's usual permission prompts apply.
From allowed-tools in the SKILL.md frontmatter.
Runs code
No scripts in the folder and no shell commands in SKILL.md (its code samples are typescript).
From the folder's file list and the shell code blocks in SKILL.md.
Network
No URLs in SKILL.md.
From URLs in SKILL.md, links to its own repository left out.
Credentials
Names no API keys, tokens, secrets or passwords.
From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.

Context cost

Define Feature Flag loads about 780 tokens when it runs. Until then it costs about 61 tokens; SKILL.md has 321 words of instructions outside code blocks.

Always · name and description, kept in context so the agent knows when to use it: ~61
When it runs · the whole SKILL.md, loaded when a task matches: ~780

Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.

Safety

Auto-check passed

The automated check found no risky patterns in SKILL.md.

Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.

SKILL.md

The full file from macro-inc/macro at commit 39f3c91, republished under its AGPL-3.0 licence (© macro-inc). 321 words, ~780 tokens.

Download SKILL.mdSave it as .claude/skills/define-feature-flag/SKILL.md (or your agent's skills folder).

name: define-feature-flag
description: Define a frontend feature flag with `defineFlag` and wire its readers. Use when adding, suggesting, or changing a feature flag, PostHog flag, `ENABLE_*` env flag, `useFeatureFlag`, `isFeatureEnabled`, or `ShowFeatureFlag`.

Define a frontend feature flag

Frontend only. Registry: apps/web/src/lib/core/constant/featureFlags.ts. There is no shared backend flag system.

1. Remote or env-only?

	Remote	Env-only
Source of truth	PostHog in deployed envs	`default`, optionally overridden by env
Discriminator	`key` present	no `key`
`env`	optional local override	optional override of `default`
`default`	omit / `undefined` to fall through to PostHog	required
Readers	`useFeatureFlag`, `ShowFeatureFlag`, `isFeatureEnabled`	`isFeatureEnabled` only

Most product rollouts are remote. Use env-only when there is no PostHog flag and never will be (compile-time / local kill switch).

Ask before assuming. If the user said "flag it" and did not mention PostHog, prefer remote and confirm.

2. Define it

Add one defineFlag next to its neighbors. Do not add ENABLE_*_FLAG / _OVERRIDE / ENABLE_*() triples or a raw PostHog string at the call site.

key (remote): kebab-case, named after the question (enable-foo, disable-browser-turso-cache). Export the object in matching camelCase (enableFoo).
env: the name after VITE_, e.g. 'ENABLE_FOO' → VITE_ENABLE_FOO.
default: used when env is unset. On a remote flag, false is a real override and skips PostHog. On-in-dev / on-in-local is DEV_MODE_ENV || undefined or LOCAL_ONLY || undefined, not the boolean itself.
Never invert on the flag object. If the product question is "disable X", invert at the call site (!isFeatureEnabled(disableX)).
Env-only exports that are used as if (ENABLE_FOO) must be the boolean: defineFlag({ env, default }).enabled. The object is always truthy.

export const enableFoo = defineFlag({
  key: 'enable-foo',
  env: 'ENABLE_FOO',
  default: DEV_MODE_ENV || undefined,
});

export const ENABLE_BAR = defineFlag({
  env: 'ENABLE_BAR',
  default: false,
}).enabled;

Do not create the PostHog flag. Ask which project / environment it should live in and wait.

3. Read it

const foo = useFeatureFlag(enableFoo); // component: foo().enabled
<ShowFeatureFlag flag={enableFoo}>{...}</ShowFeatureFlag>
isFeatureEnabled(enableFoo)            // queries, helpers, env-only

A thin useXFlag wrapper around useFeatureFlag(flag) is fine when several call sites share the same read. Compose flags in the wrapper (calendar search requires calendar UI), not on the flag object.

useFeatureFlag / ShowFeatureFlag take a RemoteFlag. Passing an env-only flag is a type error.

Don't

Migrate existing FLAG / OVERRIDE / string useFeatureFlag call sites unless you are already changing that flag or were asked to.
Invent a second helper (resolveFeatureFlag for new flags, a global flags.foo map, .use() / .Show() on the object).

Files

Just SKILL.md in .claude/skills/define-feature-flag of macro-inc/macro.

Open the folder on GitHubat commit 39f3c91

Compare with similar skills

Define Feature Flag next to the 5 skills that share the most tags, products or categories with it. Stars are the repository's; “used in” counts other GitHub owners with a copy.

Define Feature Flag compared with similar skills
Skill	Stars	Used in	Tokens	Auto-check	Licence	Repo updated
Define Feature Flag this skillmacro-inc/macro	4.6k	—	~780	Automated safety check: Pass	AGPL-3.0	today
Compare Array Bundle SizePostHog/posthog-js	613	—	~599	Automated safety check: Pass	Custom licence	today
Integration Astro Staticwill-be-done/will-be-done	152	—	~636	Automated safety check: Pass	AGPL-3.0	5 days ago
Posthog Instrumentationtrycompai/crm	11k	—	~420	Automated safety check: Pass	MIT	26 days ago
Designlang TokensManavarya09/design-extract	4.2k	—	~214	Automated safety check: Pass	MIT	8 days ago
Quill CodePostHog/code	179	—	~1.1k	Automated safety check: Pass	MIT	2 mo ago

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Questions about Define Feature Flag

What does Define Feature Flag do?

Define a frontend feature flag with defineFlag and wire its readers. Define Feature Flag is an agent skill from macro-inc/macro. Define a frontend feature flag with defineFlag and wire its readers.

When should I use Define Feature Flag?

Define Feature Flag fits situations like: changing a feature flag; ENABLE env flag; isFeatureEnabled; showFeatureFlag.

How do I install Define Feature Flag in Claude Code?

Run `npx skills add macro-inc/macro --skill define-feature-flag -a claude-code`. Or copy the skill folder (.claude/skills/define-feature-flag in macro-inc/macro) into .claude/skills/define-feature-flag in your project. Claude Code loads it when a task matches its description.

How do I install Define Feature Flag in Codex?

Run `npx skills add macro-inc/macro --skill define-feature-flag -a codex`. Or copy the skill folder (.claude/skills/define-feature-flag in macro-inc/macro) into .agents/skills/define-feature-flag in your project. Codex loads it when a task matches its description.

Can I use Define Feature Flag in Cursor, Gemini CLI or GitHub Copilot?

Cursor, Gemini CLI, GitHub Copilot and OpenCode also load SKILL.md folders. With the skills CLI, run `npx skills add macro-inc/macro --skill define-feature-flag -a cursor` (or -a gemini-cli, github-copilot or opencode for the others). To copy it by hand, put the folder in .cursor/skills/define-feature-flag, .gemini/skills/define-feature-flag, .github/skills/define-feature-flag and .opencode/skills/define-feature-flag in your project.

What does Define Feature Flag need to run?

SKILL.md names no scripts, command-line tools or credentials: Define Feature Flag is instructions for the agent only.

Does Define Feature Flag access the network?

SKILL.md contains no URLs. Any network use would come from the scripts or tools the agent runs. This is read from the text; nothing was executed.

Is Define Feature Flag safe to install?

Our automated static check of SKILL.md found no risky patterns, such as piping downloads into a shell, reading credential files or hidden Unicode. It is not a guarantee. Review the folder before installing.

What licence does Define Feature Flag use?

Define Feature Flag is published under the AGPL-3.0 licence (the repository's licence). It allows redistribution, so the full SKILL.md is shown on this page.

How many tokens does Define Feature Flag use?

About 780 tokens (SKILL.md is roughly 3.1k characters). Agents keep only the skill's name and description in context until a task matches; then they load SKILL.md in full.

What are the alternatives to Define Feature Flag?

Skills that share tags, products or a category with Define Feature Flag: Compare Array Bundle Size (PostHog/posthog-js, 613 stars), Integration Astro Static (will-be-done/will-be-done, 152 stars), Posthog Instrumentation (trycompai/crm, 11k stars) and Designlang Tokens (Manavarya09/design-extract, 4.2k stars). The comparison table on this page puts their stars, adoption, token cost, safety result and licence side by side.

Who maintains Define Feature Flag?

macro-inc (a GitHub organization) maintains it in macro-inc/macro, which has 4,578 GitHub stars. The repository holds 19 skills in this directory. The repository was last updated on October 7, 2026.

Source: macro-inc/macro on GitHub. Facts on this page come from the repository at the commit we read; the author's words are quoted as theirs.

Define Feature Flag

Install Define Feature Flag

Facts

At a glance

What it does

When your agent uses it

Example prompts

Workflow steps

What it can do on your machine

Tool permissions

Runs code

Network

Credentials

Context cost

Safety

SKILL.md

Define a frontend feature flag

1. Remote or env-only?

2. Define it

3. Read it

Don't

Files

Compare with similar skills

Similar skills

Compare Array Bundle Size

Integration Astro Static

Posthog Instrumentation

Designlang Tokens

Quill Code

Storybook Stories

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Cloud Storage Hexagonal Architecture

Collab Surface Core

Questions about Define Feature Flag

Install Define Feature Flag

Facts

At a glance

What it does

When your agent uses it

Example prompts

Workflow steps

What it can do on your machine

Tool permissions

Runs code

Network

Credentials

Context cost

Safety

SKILL.md

Define a frontend feature flag

1. Remote or env-only?

2. Define it

3. Read it

Don't

Files

Compare with similar skills

Similar skills

More from macro-inc/macro

Related

Questions about Define Feature Flag