Flags Sdk
Teaches Claude how to set up and work with the Flags SDK, a feature flags toolkit for Next.js and SvelteKit that treats flags as callable functions instead of string keys. The skill includes detailed workflows for creating flags end-to-end with Vercel Flags (including CLI commands like `vercel flags add` and env var setup), integrating third-party providers through adapters (Statsig, LaunchDarkly, PostHog), and implementing the precompute pattern to keep pages static. What makes this useful is the step-by-step agent workflow that checks project state first, then runs the actual commands rather than leaving them as next steps. Covers both App Router and Pages Router in Next.js, plus SvelteKit integration and the Vercel Toolbar setup.
- skills.sh installs
- 2.7K
- GitHub stars
- 628
- last updated
- Aug 21, 2026
Install
$ npx -y skills add vercel/flags --skill flags-sdk --agent claude-codeInstalls into .claude/skills of the current project.
Files
Set up and use the Flags SDK
The Flags SDK (flags npm package) is a feature flags toolkit for Next.js and SvelteKit. It turns each feature flag into a callable function, works with any flag provider via adapters, and keeps pages static using the precompute pattern. Vercel Flags is the first-party provider; its adapter is @flags-sdk/vercel.
- Docs: https://flags-sdk.dev
- Repo: https://github.com/vercel/flags
This skill covers the code. Planning a flag, choosing between the Flags SDK, @vercel/flags-core, and OpenFeature, and managing flags in the dashboard or with the vercel flags CLI belong to the vercel-flags skill. Archiving a flag, deleting it, or removing a variant requires the checks in that skill (remove the code first, confirm no evaluations over the Skew Protection window, archive before rm); do not run those commands without it. If it is not available, suggest npx skills add vercel/flags@vercel-flags (do not auto-install) and run vercel flags <cmd> --help in the meantime. For a project on another framework, @vercel/flags-core replaces this SDK (Core SDK).
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- Repository
- github.com/vercel/flags
- Categories
- Frontend Development, Backend & APIs, Testing & QA, Documentation, Cloud & Infrastructure, CLI & Terminal
- First seen
- Apr 16, 2026
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