Since about two days ago, the Claude-4-Sonnet (thinking) model has been extremely slow — with an average TPS around 0.3, which makes it nearly unusable for productive work.
The non-thinking version of Claude-4-Sonnet is significantly faster and works fine.
Please look into this — the performance degradation is really noticeable and slows down everything.
in general the TPS depends mostly on the AI provider, Anthropic and their regional load in your area. Naturally its not good to see TPS dropping.
Could you check following to exclude potential other causes:
Have you used up your 500 included requests per month?
What amount of tokens did the chat have when it started getting slow?
Can you reproduce the issue with a new chat? (With privacy mode disabled for this one request, so the Cursor Team can review the process, then turn it back on and post here the Request ID)
I can confirm that for the last two days, the issue has been the same. Before that, we had messaging that there are vertex rate limits, then just 1 token per second speed. It’s in fast requests pay-as-you-go mode. Sometimes it gets better, but I feel that Anthropic could make the model dumber to fix the load. It usually happens late at night. And in the mornings. Most likely when Europe and Asia are heavily using API. I’m in Toronto, Canada.
Yeah. Same here. It is borderline unusable. I am trying to work with Claude 4 in the MAX mode. With usage-based spend. Seems to depend on time of the day. It was working fine in the morning, but around 3PM Pacific - TPS just tanked.
It’s possible that Claude is limiting competitors to force users to switch to their own coding tool. They released Claude code for all Pro users. It’s hard to say. I will definitely install Claude Code in terminal and try to switch that when cursor speed is impossible.
I have been observing the same problem over the last couple of days. Sometimes it’s super-fast, sometimes it’s super-slow. Sometimes completely unusable. Not sure where the source of the problem is.
As most users are not affected by this issue, more information is needed to check the cause.
If your requests are repeatedly slow could you please reproduce it in one request with privacy mode disabled so the Cursor Team can look into the details as otherwise they don’t see that.
It’s been a week since then. Since that time, I’ve been experiencing these kinds of TPS drops every day, for what seems to be around 30 minutes to 1.5 hours per day, during which the performance becomes completely unacceptable.
In my opinion, even if the root cause lies with Anthropic, Cursor should be cutting off connections that are too slow.
Right now, you’re making me wait 15 minutes for a single response — which I’ll likely cancel midway — and I still get charged for faulty requests that are ultimately useless to me.
I get several to a dozen such requests every day. Let’s assume it’s just 5. If this were to happen daily, I’d be losing around 150 requests per month…
Especially since this seems to be a global issue. Other users mentioned experiencing it in Toronto and in the Pacific Time zone.
I’m based in Europe — Warsaw, Poland — and it feels like these drops happen between 10 AM and 2 PM CEST.
@rterry please file a full Bug report in a separate thread as this is not related to the issues above. The Bug report allows us to check what is happening as your text suggests. It’s not with Claude but with some tools, make sure to add a request ID, preferably with disabled privacy setting for this one request so the Cursor Team can investigate as otherwise they have no access to the tool calls in your request