License Setup

Add your license key

Put it in .env.local in the root of your project:

REUI_LICENSE_KEY=your-license-key-here

Point components.json at the @reui registry

Update components.json to use the authenticated @reui registry config:

{
  "registries": {
    "@reui": {
      "url": "https://reui.io/r/{style}/{name}.json",
      "headers": {
        "Authorization": "Bearer ${REUI_LICENSE_KEY}"
      }
    }
  }
}

The shadcn CLI expands ${REUI_LICENSE_KEY} from your environment, so leave it as a variable here. A ReUI MCP server entry is a separate config with its own rules, and they differ by client: Claude Code expands ${VAR} in .mcp.json, Cursor and VS Code only understand the env: prefix (${env:NAME}, and VS Code also takes an ${input:...} prompt), OpenCode uses single braces with no dollar sign ({env:NAME}), Codex reads the value from bearer_token_env_var, and Antigravity's mcp_config.json documents no substitution at all, so there the real token gets pasted in. Check your agent's guide before copying this line across, and create a token at Account → MCP.

Install registry items

Install from the same namespace:

pnpmnpmyarnbun
pnpm dlx shadcn@latest add @reui/c-data-grid-1
Copy

Free components continue to work with the authenticated config, so you do not need a second registry namespace.

Put components.json in the package, not the repo root

Every workspace needs its own components.json, and the @reui registry block belongs in the one you install from:

{
  "aliases": {
    "components": "@workspace/ui/components",
    "ui": "@workspace/ui/components",
    "lib": "@workspace/ui/lib",
    "hooks": "@workspace/ui/hooks",
    "utils": "@workspace/ui/lib/utils"
  },
  "registries": {
    "@reui": {
      "url": "https://reui.io/r/{style}/{name}.json",
      "headers": {
        "Authorization": "Bearer ${REUI_LICENSE_KEY}"
      }
    }
  }
}

The aliases are what land the files in packages/ui instead of in an app.

Keep the key next to it

The CLI loads .env.local from the directory it runs in and does not walk up to parent folders, so a key kept only in the repo root's .env.local is never seen. That is the Registry "@reui" requires the following environment variables error, and it stops before any request is made:

REUI_LICENSE_KEY=your-license-key-here

Run the install from the package

cd packages/ui
npx shadcn@latest add @reui/c-data-grid-1

Or stay at the repo root and point the CLI at the package, which is what it suggests itself when run from there:

pnpmnpmyarnbun
pnpm dlx shadcn@latest add -c packages/ui @reui/c-data-grid-1
Copy

Running from a directory whose components.json has no @reui block (the root, or an app) is the other way this fails: the CLI falls back to shadcn's public directory entry for @reui, which carries no license header, so reui.io answers You are not authorized to access the item even though the key is set.