Model Context

Model Context is the foundation of intelligence in assistant-ui components. It provides configuration and capabilities to the assistant through a context provider system.

Core Concepts

System Instructions

System instructions define the base behavior and knowledge available to the assistant. These can be provided in several ways:

import {
  useAssistantInstructions,
  makeAssistantVisible,
} from "@assistant-ui/react";

// Via useAssistantInstructions
useAssistantInstructions("You are a helpful assistant...");

// Via makeAssistantVisible
const ReadableComponent = makeAssistantVisible(MyComponent);
// Automatically provides component HTML as system context

Tools

Tools are functions that the assistant can use to interact with your application. They can be provided through various mechanisms:

import {
  makeAssistantVisible,
  makeAssistantTool,
  tool,
  useAssistantRuntime,
} from "@assistant-ui/react";
import { z } from "zod";

// Via makeAssistantVisible's clickable option
const ClickableButton = makeAssistantVisible(Button, {
  clickable: true, // Provides a click tool
});

// Via makeAssistantTool
const submitForm = tool({
  parameters: z.object({
    email: z.string().email(),
    name: z.string(),
  }),
  execute: async ({ email, name }) => {
    // Implementation
    return { success: true };
  },
});

const SubmitFormTool = makeAssistantTool(submitForm);

// Use in your component
function Form() {
  return (
    <div>
      <form>{/* form fields */}</form>
      <SubmitFormTool />
    </div>
  );
}

Context Provider System

The context provider system allows components to contribute to the model context. Here's a typical usage pattern:

import { useAssistantRuntime, tool } from "@assistant-ui/react";
import { useEffect } from "react";
import { z } from "zod";

function MyComponent() {
  const assistantRuntime = useAssistantRuntime();

  // Define tool using the tool() helper
  const myTool = tool({
    parameters: z.object({
      query: z.string(),
    }),
    execute: async ({ query }) => {
      const result = await searchDatabase(query);
      return { result };
    },
  });

  useEffect(() => {
    // Register context provider
    return assistantRuntime.registerModelContextProvider({
      getModelContext: () => ({
        system: "You are a helpful search assistant...",
        tools: { myTool },
      }),
    });
  }, [assistantRuntime]); // Re-register if runtime changes

  return <div>{/* component content */}</div>;
}

Provider Composition

Multiple providers can be registered, and their contexts will be composed:

System instructions are concatenated
Tool sets are merged
Nested readable components only contribute their context at the outermost level

Best Practices

System Instructions
- Keep them focused and specific to the component's purpose
- Use useAssistantInstructions for explicit instructions
- Let makeAssistantVisible handle component structure
Tools
- Use the tool() helper to define tool schemas and behavior
- Prefer makeAssistantTool for reusable tools
- Handle errors gracefully
- Consider async operations and loading states
- Use the built-in click tool when possible
Context Management
- Register providers in useEffect for proper cleanup
- Clean up providers when components unmount
- Avoid deeply nested readable components
- Consider performance implications of large HTML structures