OpenAI drops Cursor, Anthropic offers more Claude compute

OpenAI told Cursor it will stop serving models through the editor on November 12. Cursor CEO Michael Truell said August 29 that OpenAI models handle about 5% of user traffic on the platform, and that talks with OpenAI are ongoing.

That's the first real number attached to the cutoff. Cursor runs on multiple model providers, so losing one at 5% share doesn't break anyone's workflow. What it does is put a dollar figure on how much OpenAI is willing to give up to pull its models out of a tool it doesn't control.

Anthropic didn't wait to find out how the talks end. The same night, co-founder Tom Brown said Cursor has been a partner since Sonnet 3.5 and that Anthropic will keep raising compute allocations for Claude models inside Cursor, per Anthropic's reply as reported by Daily Guardian.

The timing says more than the words. Brown didn't wait for a request or a gap in service, he moved before OpenAI's exit date even arrives. For anyone building on top of someone else's model API, that's the actual lesson: the provider that shows up uninvited the night a competitor pulls out is telling you where it wants your default routing to land. Cursor's own numbers say it can absorb the loss. Whether it wants to is a separate question, and neither company has answered it yet.