C1 by Thesys

In plain words

C1 is a Generative UI API that enables large language models to respond with interactive user interface elements like charts, forms, and cards in real time. It integrates with any LLM, framework, or MCP through a minimal code setup. The tool is designed for developers building AI applications who want to reduce UI development overhead and accelerate deployment timelines.

written from the facts on this page · September 2026

From the sources

C1 is a Generative UI API that augments LLMs to respond with interactive UI like charts, forms, cards, and more, in real time. It integrates seamlessly with any LLM, framework, or MCP in just 2 lines of code. Ship AI apps 10X faster with 80% less UI overhead.

Frontend infrastructure for AI products. Build dynamic, real-time UIs with C1 Generative UI API.

Thesys provides the Generative UI foundation for teams building AI products that go beyondfrom thesys.dev

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