Get Started with Freesail

Agent Driven UI

• Let your AI agents generate dynamic UI in real-time to interact with users.
• Avoid user fatigue associated with walls of text in AI conversations.
• Grab user attention with dynamic UI.
• Freesail is an open source SDK based on the A2UI protocol.

Contract First

A critical challenge in Agent Driven UI is the risk of agents hallucinating invalid code or breaking UI layouts.

• Freesail solves this by implementing a “Contract-First” philosophy.
• Instead of writing code, the agent makes use of the UI capabilities defined in a JSON schema (A2UI Catalog).

Batteries Included

Freesail achieves highly performant A2UI via a 3-node architecture:

• The Agent: The “brain” of the operation (e.g., LangChain) that makes decisions about what UI to display via Model Context Protocol (MCP) tools.
• Freesail Gateway: A standalone MCP and Express server that validates the agent’s output against the catalog schema and seamlessly streams A2UI messages to the client, and user actions back to the agent.
• Freesail Renderer: The stateful presentation layer that translates the incoming A2UI messages into actual UI components (currently React), manages the local data model, and handles offline queueing and user interactions.

Bring Your Own UI

You can use Freesail to build your own Agent Driven UI components. UI components are fully customizable with custom styles and themes.

• Empower your agents to render your own Agent Driven UI components by defining and registering custom Agent Driven UI components with Freesail.
• Use, share or sell your Agent Driven UI components!

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