I hate that their model ids don't change as they change the underlying model. I'm not sure how you can build on that.
% curl https://api.deepseek.com/models \
-H "Authorization: Bearer ${DEEPSEEK_API_KEY}"
{"object":"list","data":[{"id":"deepseek-chat","object":"model","owned_by":"deepseek"},{"id":"deepseek-reasoner","object":"model","owned_by":"deepseek"}]}Oh hey, quality improvement without doing anything!
(unless/until a new version gets worse for your use case)
Anthropic has done similar before (changing model behavior on the same dated endpoint).
Agree that having datestamps on model ids is a good idea, but it's open source, you can download the weights and build on those. In the long run, this is better than the alternative of calling API of a proprietary model and hoping it doesn't get deprecated.