SiteUI Components & Libraries · Agent UI
21st.dev Agent Elements
Open registry of agent UI primitives: chat shell, tool-call cards for bash/edit/search/todo, clarifying questions and streaming markdown.
Why it’s a gem
Tool-call card primitives are the hardest part of an agent UI and nobody else ships them
- Author
- 21st.dev (@21stdev)
- Type
- Website
- License
- open-source
- Added
- Aug 17, 2026
- Domain
- agent-elements.21st.dev
