Transforms LLM text responses into interactive UI components in real-time.
Accelerates AI frontend development and enhances user engagement.
OpenAI-compatible API, works with various LLMs and supports custom components.
Pricing: Free plan available
Best for: Growing teams
Pros & Cons
Pros
Significantly improves user engagement compared to text-only responses.
Accelerates AI frontend development by up to 10x and reduces costs by 80%.
Provides a flexible and adaptive UI that responds dynamically to user intent and context.
Compatible with existing AI stacks and various LLMs, preventing vendor lock-in.
Offers robust security and compliance features for enterprise use.
Cons
LLM tokens are billed separately, adding to the overall cost.
Requires integration with a React SDK, which might be a barrier for non-React users.
Artifacts API is billed separately from core C1 API calls.
Preview
Key Features
Generates interactive UI components (charts, forms, cards, lists, tables, slides, reports) from LLM responses.OpenAI-compatible API endpoint for easy integration.Supports multiple LLMs including OpenAI, Anthropic, and Google.React SDK for rendering generated UI.Customizable UI to match brand and design systems.Supports all tool-calls for connecting to external data (databases, documents, APIs).Allows integration of custom React components with custom logic and styling.Configurable actions, callbacks, and workflows.
Pricing Plans
Free
$0/month
Free credits for developers exploring Generative UI
5K C1 API calls / month
Upgrade for additional usage
LLM credits worth $10 free
Style customizations
Supports all popular LLMs
Discord Community support
Build
$49/month
Usage-based plan for teams ready to ship with GenUI.
25K C1 API calls / month
$0.002 per call after that
Everything in Free
Higher request priority
Higher rate limits
Email Support
Grow
$499/month
Usage-based plan for teams ready to ship with GenUI.
500K C1 API calls / month
$0.001 per call after that
Everything in Build
Highest request priority
Highest rate limits
Priority Slack Support
Dedicated Solutions engineer (Add-on)
SSO SAML (Coming Soon)
Scale
Contact sales
Secure deployments for large orgs with scaled needs.
Thesys offers C1, an API middleware that transforms large language model (LLM) text responses into dynamic, interactive user interfaces. Instead of receiving plain text, AI applications can respond with structured UI components like charts, forms, cards, lists, tables, slides, and reports, rendered in real-time. This allows developers to build AI-powered applications with rich, adaptive frontends without extensive manual UI coding.
C1 is designed for AI-native teams building agents, copilots, and tools where use cases evolve rapidly and static UIs are insufficient. It integrates as an OpenAI-compatible endpoint, working with various LLMs (OpenAI, Anthropic, Google) and allowing for custom React components and branding. The platform aims to accelerate AI frontend development, improve user engagement, and provide enterprise-grade security and compliance.
The product's core value lies in enabling AI applications to deliver engaging, context-aware, and personalized user experiences by dynamically generating UI based on LLM outputs, adapting to logic, state, and user behavior.
C1 by Thesys is an API middleware that augments LLMs to respond with interactive UI in real-time instead of text. It turns LLM responses into live, adaptive user interfaces using structured UI components like forms, tables, charts, and layouts, which can be rendered with the C1 React SDK. It works with multiple LLMs and supports custom design systems.
How much does Thesys cost?
Thesys offers a freemium model. There's a Free plan with 5K C1 API calls/month and $10 free LLM credits. Paid plans include 'Build' at $49/month for 25K C1 API calls, and 'Grow' at $499/month for 500K C1 API calls. Enterprise plans have custom pricing. LLM tokens are billed separately at the same rates as the model providers, and Artifacts API is also billed separately at $0.01 per page operation after 100 free pages/month.
Is Thesys free?
Yes, Thesys offers a free plan for individuals, which includes 5,000 C1 API calls per month and $10 in free LLM credits, allowing developers to explore Generative UI without initial cost.
Who is Thesys for?
Thesys is for AI-native teams building software agents, copilots, and tools where use cases evolve quickly and static UIs are insufficient. It's ideal for developers, product teams, and builders creating dynamic, task-specific interfaces that adapt to logic, state, and user behavior.