How to Configure an AI API Base URL in Cursor

Cursor can work with OpenAI-compatible third-party APIs. After buying credit and creating an API Key, you can use one endpoint to test GPT, Claude, Gemini, and coding models.

Who this is for

• Developers who want lower AI coding costs
• Cursor users testing multiple model families
• Small teams that need lightweight AI coding workflows
• Users who want a simple API credit setup

What you need

• A valid API Key
• OpenAI-compatible Base URL: https://api.cheng-zi-ai.com/v1
• Cursor installed
• A model name such as gpt-5.3-codex

Setup steps

1. Open Cursor settings.
2. Find model or API provider settings.
3. Select OpenAI Compatible or Custom API.
4. Paste your API Key.
5. Set Base URL to https://api.cheng-zi-ai.com/v1.
6. Enter an available model name.
7. Save and send a short test prompt.

Common errors

• 401 Unauthorized: wrong API Key, extra spaces, or inactive key.
• 404 Not Found: missing /v1 or incorrect model name.
• Model unavailable: the selected model is not enabled for the key.
• Slow response: try a lighter model or test outside peak hours.

Which credit pack should you choose?

Start small if you only need to test Cursor. Choose a larger credit pack if you use AI coding every day and want fewer top-ups.

Risk note

Third-party API relay services are best for personal development, small-team testing, and lightweight workflows. Avoid uploading sensitive keys, customer data, or unreleased source code.