CopilotKit v1 to v2 Migration Skill

Live Documentation (MCP)

This plugin includes an MCP server (copilotkit-docs) that provides search-docs and search-code tools for querying live CopilotKit documentation and source code. Useful for looking up current v2 API signatures during migration.

• Claude Code: Auto-configured by the plugin's .mcp.json -- no setup needed.
• Codex: Requires manual configuration. See the [copilotkit-debug skill](../copilotkit-debug/SKILL.md#mcp-setup) for setup instructions.

Overview

CopilotKit v2 is a ground-up rewrite built on the AG-UI protocol (@ag-ui/client / @ag-ui/core). Users continue to install and import @copilotkit/ packages -- the v2 changes are exposed through the same package names (under their /v2 subpaths) with updated APIs (new hook names, component names, runtime configuration). The underlying @ag-ui/ packages are an internal implementation detail re-exported through @copilotkit/react-core/v2, so users never need to install them directly.

Migration Workflow

1. Audit Current Usage

Scan the codebase for all v1 imports and API usage:

@copilotkit/react-core    -> hooks, CopilotKit provider, types
@copilotkit/react-ui      -> CopilotChat, CopilotPopup, CopilotSidebar
@copilotkit/react-textarea -> CopilotTextarea (removed in v2)
@copilotkit/runtime       -> CopilotRuntime, service adapters, framework integrations
@copilotkit/runtime-client-gql -> GraphQL client, message types
@copilotkit/shared         -> utility types, constants
@copilotkit/sdk-js         -> LangGraph/LangChain SDK

2. Identify Deprecated APIs

Key hooks and components to find and replace:

3. Map to v2 Equivalents

Refer to references/v1-to-v2-migration.md for detailed before/after code examples.

4. Update Package Dependencies

The @copilotkit/* package names stay the same. v2 does not introduce new package names -- the v2 APIs ship from the /v2 subpath of the existing packages (@copilotkit/react-core/v2, @copilotkit/runtime/v2). There is no @copilotkit/react or @copilotkit/agent package. Update to the latest v2 versions:

@copilotkit/react-core         -> @copilotkit/react-core (v2 symbols under the /v2 subpath)
@copilotkit/react-ui           -> chat components move to @copilotkit/react-core/v2; react-ui contributes only styles in v2
@copilotkit/react-textarea     -> removed (no v2 equivalent)
@copilotkit/runtime            -> @copilotkit/runtime (v2 symbols under the /v2 subpath)
@copilotkit/runtime-client-gql -> removed (replaced by AG-UI protocol; @ag-ui/client types are re-exported from @copilotkit/react-core/v2)
@copilotkit/shared             -> @copilotkit/shared (same package)
@copilotkit/sdk-js             -> removed (BuiltInAgent now ships from @copilotkit/runtime/v2)

5. Update Runtime Configuration

The v1 CopilotRuntime accepted service adapters (OpenAI, Anthropic, LangChain, etc.) and endpoint definitions. The v2 CopilotRuntime accepts AG-UI AbstractAgent instances directly.

v1 pattern (service adapter + endpoints):

import { CopilotRuntime, OpenAIAdapter } from "@copilotkit/runtime";
const runtime = new CopilotRuntime({ actions: [...] });
// used with framework handlers like copilotRuntimeNextJSAppRouterEndpoint() (Next.js), etc.

v2 pattern (agents + Hono endpoint):

import {
  CopilotRuntime,
  BuiltInAgent,
  createCopilotHonoHandler,
} from "@copilotkit/runtime/v2";
const runtime = new CopilotRuntime({
  agents: { myAgent: new BuiltInAgent({ model: "openai/gpt-4o" }) },
});
const app = createCopilotHonoHandler({ runtime, basePath: "/api/copilotkit" });

Use createCopilotHonoHandler (from @copilotkit/runtime/v2) as the canonical Hono endpoint factory. createCopilotEndpoint is a deprecated alias for it -- avoid it in new code. For Express, use createCopilotExpressHandler from @copilotkit/runtime/v2/express (createCopilotEndpointExpress is its deprecated alias).

6. Update Provider

The provider component keeps the name CopilotKit -- only the import path changes. The package root (@copilotkit/react-core) is the legacy v1 provider; the /v2 subpath is the migration target.

v1 (root import):

import { CopilotKit } from "@copilotkit/react-core";
<CopilotKit runtimeUrl="/api/copilotkit">{children}</CopilotKit>;

v2 (/v2 import):

import { CopilotKit } from "@copilotkit/react-core/v2";
<CopilotKit runtimeUrl="/api/copilotkit">{children}</CopilotKit>;

Note: @copilotkit/react-core/v2 also exports a CopilotKitProvider component. Do not migrate to it -- it is a functionality subset of CopilotKit, which is the compatibility bridge across v1 and v2 and accepts every CopilotKitProvider prop.

7. Verify

• Run the application and check for runtime errors
• Verify all agent interactions work (chat, tool calls, interrupts)
• Check that tool renderers display correctly
• Confirm suggestions load and display

Quick Reference