Before you start
You need a free 21st.dev API key, and each tool needs adding once: for 21st, run npx @21st-dev/cli@latest init --client [your client] and paste the key into the config it prints. Front-End Checklist is a hosted server at https://mcp.frontendchecklist.io with no key. Chrome DevTools MCP runs through npx chrome-devtools-mcp@latest and needs Chrome. On 21st's free plan, search is unlimited but you can fetch component code twice a day. Chrome DevTools MCP can see and change anything in that browser, so don't sign in to accounts you care about while it runs.
Look at options first
Searching is free and fetching code is not, so choose before you fetch.
Say to Claude CodeUse 21st to find three pricing table components with a monthly/yearly toggle that suit a Tailwind project. Describe each one and wait for my pick. Don't add anything yet.
Add the one you pick
Tell it what to reuse so it doesn't bring in duplicates.