Best AI SDKs for Tailwind CSS

21st is a development platform designed to help engineers quickly build and deploy AI agents inside their applications. The platform provides a specialized SDK that simplifies the process of defining agent behavior, integrating tools, and connecting AI models. Developers can create agents using familiar technologies such as Next.js, React, TypeScript, Python, and Node.js, making integration straightforward for modern applications. Once an agent is defined, the platform allows it to be deployed with a single command while automatically handling infrastructure requirements. 21st provides sandboxed execution environments through E2B sessions, ensuring that agent operations run securely and independently. The platform includes a ready-to-use chat interface component that can be embedded directly into an app for user interaction. Additional features include token streaming, conversation history, tool execution, and built-in observability for debugging and monitoring. Developers can replay sessions and trace tool calls to better understand how agents behave during execution. The system also supports spend limits, authentication controls, and rate limiting to manage AI usage across users. By combining development tools with managed infrastructure, 21st helps teams launch scalable AI agents without building complex backend systems.