AI SDK - Cursor Harness

The @ai-sdk/harness-cursor package adapts Cursor CLI to the AI SDK harness abstraction through the Agent Client Protocol (ACP).

Setup

npm install @ai-sdk/harness @ai-sdk/harness-cursor @ai-sdk/sandbox-vercel

Create a Cursor user API key and set CURSOR_API_KEY, or pass it directly with createCursor({ auth: { CURSOR_API_KEY: token } }). The key authenticates Cursor CLI in the sandbox regardless of how Cursor is configured to authenticate to the model provider.

Usage

import { HarnessAgent } from '@ai-sdk/harness/agent';
import { cursor } from '@ai-sdk/harness-cursor';
import { createVercelNetworkSandboxSession } from '@ai-sdk/sandbox-vercel';

const agent = new HarnessAgent({
  harness: cursor,
});

const sandboxSession = await createVercelNetworkSandboxSession({
  runtime: 'node24',
  ports: [4000],
  template: await agent.getSandboxTemplate(),
});
const session = await agent.createSession({ sandboxSession });

try {
  const result = await agent.generate({
    session,
    prompt: 'Inspect this project and summarize its purpose.',
  });
  console.log(result.text);
} finally {
  await session.destroy();
  await sandboxSession.destroy();
}

The adapter installs Cursor CLI inside the sandbox with Cursor's official installer. The sandbox must provide network access and at least one exposed TCP port.

Cursor controls model-provider authentication in its own settings. For AI Gateway, configure Cursor's OpenAI API key with an AI Gateway key and set Override OpenAI Base URL to https://ai-gateway.vercel.sh/cursor/v1. The auth setting accepts the shared ACP modes auto, direct, and ai-gateway; explicit direct and ai-gateway values emit a configuration reminder, while auto does not. The setting cannot change Cursor's account configuration.

See the Cursor harness documentation for settings, tools, and limitations.