Cursor OpenAI Proxy

Local OpenAI-compatible chat completions API backed by the official Cursor TypeScript SDK. Runs in the system tray.

Prerequisites

1. Node.js 22.13+
2. A Cursor API key from Dashboard → API Keys

Install & run

npm install
npm run dev

Production:

npm run build
npm start

Background (hidden window on Windows):

npm run build
npm run start:bg

Auth (required)

Every OpenAI client must send your Cursor key as a Bearer token:

Authorization: Bearer cursor_...

Endpoint	Behavior
GET / or GET /v1	200 only if Bearer auth works and Cursor API is reachable (Cursor.me)
GET /v1/models	Models from Cursor.models.list() (Bearer required)
POST /v1/chat/completions	Chat via @cursor/sdk Agent (Bearer required)

Status UI: http://127.0.0.1:4646/ui/

Config file: %APPDATA%\cursor-openai-proxy\config.json (host/port only).

Client setup

• Base URL: http://127.0.0.1:4646/v1
• API key: your Cursor API key (the client sends it as Authorization: Bearer …)

Example

curl http://127.0.0.1:4646/v1/chat/completions ^
  -H "Authorization: Bearer %CURSOR_API_KEY%" ^
  -H "Content-Type: application/json" ^
  -d "{\"model\":\"auto\",\"messages\":[{\"role\":\"user\",\"content\":\"Say hi in one sentence.\"}]}"

Live auth check:

curl -i http://127.0.0.1:4646/ ^
  -H "Authorization: Bearer %CURSOR_API_KEY%"

How it works

Requests are handled with @cursor/sdk:

• Auth probe → Cursor.me({ apiKey })
• Models → Cursor.models.list({ apiKey })
• Chat → Agent.create + agent.send (local runtime, isolated workspace under the config dir)

Notes

• Host/port changes in config require a restart.
• Default listen address: 127.0.0.1:4646
• SDK usage follows the same Cursor billing / privacy rules as IDE and Cloud Agents.