Reading agent state - Copilotkit

<Callout type="info"> This example demonstrates reading from shared state in the [CopilotKit Feature Viewer](https://feature-viewer.copilotkit.ai/pydantic-ai/feature/shared_state). </Callout>

What is this?

You can easily use the realtime agent state not only in the chat UI, but also in the native application UX.

When should I use this?

You can use this when you want to provide the user with feedback about your agent's state. As your agent's state updates, you can reflect these updates natively in your application.

Implementation

<Steps> <Step> ### Run and connect your agent <RunAndConnect components={props.components} /> </Step> <Step> ### Define the Agent State

Create your Pydantic AI agent with a stateful structure. Here's a complete example that tracks language:

```python title="agent.py"
from textwrap import dedent

from pydantic import BaseModel
from pydantic_ai import Agent, RunContext
from pydantic_ai.ag_ui import StateDeps


class AgentState(BaseModel):
    """State for the agent."""
    language: str = "english"


agent = Agent("openai:gpt-5.4-mini", deps_type=StateDeps[AgentState])


@agent.instructions()
async def language_instructions(ctx: RunContext[StateDeps[AgentState]]) -> str:
    """Instructions for the language tracking agent.

    Args:
        ctx: The run context containing language state information.

    Returns:
        Instructions string for the language tracking agent.
    """
    return dedent(
        f"""
        You are a helpful assistant for tracking the language.

        IMPORTANT:
        - ALWAYS use the lower case for the language
        - ALWAYS response in the current language: {ctx.deps.state.language}
        """
    )


app = agent.to_ag_ui(deps=StateDeps(AgentState()))

if __name__ == "__main__":