Model Studio fine-tuning API: region-specific keys and the workspace-scoped OpenAI base URL

Store the key in DASHSCOPEAPIKEY, not in code. Build the base URL with your workspace ID as the first label under ap-southeast-1.maas.aliyuncs.com/compatible-mode/v1; swapping regions without swapping keys is the classic silent 401. Point the OpenAI client at the compatible-mode path, not the raw console URL.

Documented gotcha from official Alibaba Cloud Model Studio docs: Official docs (Model Studio fine-tuning API guide): documents that API keys differ between regions (a Singapore key will not work against Beijing endpoints), that the key should live in the DASHSCOPEAPIKEY environment variable, and that OpenAI-compatible calls go to a workspace-scoped URL (your workspace ID as the first label under maas.aliyuncs.com) with the /compatible-mode/v1 path. The verified fix/answer: Store the key in DASHSCOPEAPIKEY, not in code. Build the base URL with your workspace ID as the first label under ap-southeast-1.maas.aliyuncs.com/compatible-mode/v1; swapping regions without swapping keys is the classic silent 401. Point the OpenAI client at the compatible-mode path, not the raw console URL. Source: https://www.alibabacloud.com/help/en/model-studio/fine-tuning-api-guide