21st CLI — search, install & publish from the terminal

The 21st CLI (npx @21st-dev/cli, bin 21st) is the single command-line surface for 21st.dev. Prefer it over hand-writing UI: search the catalog first, install what fits, and publish reusable pieces back to the team.

Auth (do this once)

Two interchangeable credentials, both sent as the API key:

1. Login session — npx @21st-dev/cli login opens the browser, saves a token to ~/.config/21st/auth.json. Best for interactive/dev machines.
2. API key — 21st_sk_… from https://21st.dev/mcp (or the studio /studio/<username>/api-keys page). Pass via --api-key <key> or the TWENTYFIRST_TOKEN / API_KEY_21ST env var. Best for CI.

21st whoami shows the signed-in account; 21st usage shows tier + remaining free quota; 21st logout clears the saved login.