Wiring Langgraph

LangGraph — wired via @copilotkit/runtime/langgraph. Supports LangGraph Platform deployments and self-hosted LangGraph servers.

Install

LangGraphAgent (and LangGraphHttpAgent for self-hosted AG-UI LangGraph servers) ship with @copilotkit/runtime — no separate install needed.

Minimal wire-up

import {
  CopilotRuntime,
  createCopilotRuntimeHandler,
} from "@copilotkit/runtime/v2";
import { LangGraphAgent } from "@copilotkit/runtime/langgraph";

const runtime = new CopilotRuntime({
  agents: {
    default: new LangGraphAgent({
      deploymentUrl: process.env.LANGGRAPH_URL!,
      graphId: "agent",
      langsmithApiKey: process.env.LANGSMITH_API_KEY, // optional
    }),
  },
});

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

export default { fetch: handler };

Config fields

Gotcha — deploymentUrl is NOT the CopilotKit runtime URL

The most common mistake is setting deploymentUrl to /api/copilotkit. That is the frontend↔runtime URL, not the LangGraph server. Use the actual LangGraph deployment URL.

Source: docs/content/docs/integrations/langgraph/quickstart.mdx:355.