copilotkit--copilotkit/skills/runtime/references/wiring-pydantic-ai.md

PydanticAI — wired via the bare HttpAgent from @ag-ui/client.

Install

pnpm add @ag-ui/client

Minimal wire-up

import {
  CopilotRuntime,
  createCopilotRuntimeHandler,
} from "@copilotkit/runtime/v2";
import { HttpAgent } from "@ag-ui/client";

const runtime = new CopilotRuntime({
  agents: {
    default: new HttpAgent({
      url: process.env.PYDANTIC_AI_URL ?? "http://localhost:8000/",
    }),
  },
});

const handler = createCopilotRuntimeHandler({
  runtime,
  basePath: "/api/copilotkit",
});

export default { fetch: handler };

Server side

On the Python side, PydanticAI exposes an AG-UI-compliant endpoint via its built-in ASGI adapter. The URL you pass to HttpAgent is that endpoint (e.g. an FastAPI route that returns a streaming response of AG-UI events).

Gotcha — no suffix required

Unlike LlamaIndex (/run) and Agno (/agui), PydanticAI does not mandate a specific sub-path. Whatever path your Python server mounts the AG-UI app at — use that.

Source: docs/content/docs/integrations/pydantic-ai/quickstart.mdx.