Only during exploration, even though I have my subagent and explore agent model set to composer 2.5 (not fast), it always default to 2.5 fast. Seeing as the fast variant takes ~3x more usage than the normal variant, for us on the pro/pro+ plans it can make a big difference.
Steps to Reproduce
Set the explore agent in Settings → Agents → Explore subagent model to Composer 2.5, hover and click edit, disable Fast.
Ask for any task where exploration is required, and you will see the agent is running as Composer 2.5 Fast.
Expected Behavior
The agents should be spawned as Composer 2.5 without fast mode enabled.
Hey, thanks for the report and the clear steps. This is a known regression. The explore subagent set via the UI with Fast turned off still resolves to Composer 2.5 Fast. I can reproduce it, and we’re tracking it on our side, but I don’t have an ETA yet.
This is a bad one as it actually racks up a lot of extra costs for long-horizon tasks where subagents keep getting spawned. The only solution was to switch to a non-fast model in the settings
Thanks, confirmed. This is the same regression described above, and it still reproduces on 3.6.31. We’ve reported it internally and are tracking it, but there’s no exact ETA for a fix yet.
On costs, I get it. In long tasks where subagents keep spawning, the Fast variant can really add up. As a temporary workaround, you’ve already found a good path: pick a model that doesn’t switch to Fast. I’ll post an update in this thread as soon as we have one.
I am still experiencing this issue, and unfortunately, it is happening across multiple models. It would be incredibly helpful to have a setting to completely turn off fast mode. I prioritize saving my subscription usage over generation speed.
Hey, thanks for coming back with an update. The subagent switching to Fast despite your setting is not intended behavior, and it’s not caused by anything in your configuration. We’re tracking this issue, but I can’t share an exact ETA yet.
On the original Composer 2.5 via picker case, we already made some progress, but since you’re seeing this across multiple models, it looks like a broader issue we’re still tracking separately. To pin down your exact situation, could you please share:
which models are affected where you set non-Fast but it runs as Fast
your Cursor version Settings > About or from the version window
the Request ID from a run where the subagent switched to Fast in the chat: top-right menu > Copy Request ID. If Privacy Mode is enabled, the Request ID may be unavailable
Temporary workaround: in Settings > Agents, for the explore subagent, pick a model that doesn’t have a Fast toggle. Then the usage won’t jump to 3x.
About a separate toggle to fully disable Fast, that’s a fair request. I’ll pass it along as feedback. There are similar threads already, and you can upvote them here:
I naturally did it. I’ve also added mdc rules, I’m doign everything, and from time to time I can see it spawns fast subagents. This is a problem for my token economy, I cannot afford this kind of models. I’m trying everything to avoid it, everything. Obviously I’ve selected non fast model for subagents. Looks like this bug doesn’t want be fixed because I cannot believe that we still have this problem in the agentic era where you can litterally spawn a swarm of bot to fix it. I appreciate a lot your professionalism in the terms of support but from a company like spaceX I think this is not acceptable anymore. I’m a big fan of Cursor, but these issues have me thinking about looking into other alternatives.
Hey @andeeplus, thanks for the Request ID and version, that really helped.
I checked that run. The main agent was running on Grok 4.7 High with Fast turned off. All subagents it launched were also running on Grok 4.7 High without Fast, and billing was at the standard rate. I also checked your recent subagent runs, and none of them over the past few weeks were billed as Fast.
It looks like “Fast” only shows up in the UI label, while billing still uses the standard rate. Could you send a screenshot showing exactly where you see Fast? For example, the subagent row in chat, the subagent panel itself, or the row on the Usage page at https://cursor.com/dashboard. The Usage page shows which model each request was billed under, so that’s the most reliable way to verify it. If you find a Fast entry there, send it over with the approximate time and I’ll take a closer look.
One more thing that can actually affect costs. Sometimes the main agent launches a subagent on a different, more expensive model. In one of your recent runs, it picked Claude Opus 5.5. To prevent that, go to Cursor Settings > Models and turn off any models you don’t want subagents to use. Then they’ll only be able to pick from the models that are still enabled. It’s also worth checking that list again after updates, since new models can show up enabled by default.
I get that this can really get in the way when you’re working with a limited usage budget. Once you send the screenshot, we can dig into it more.
Thanks, Dean.
I probably should have checked the dashboard first!
This is a very interesting bug, and I’m glad it was just a UI labeling issue.
I wonder if other claims similar to mine are also directly related to incorrect labeling.
Hopefully, this helps with the investigation.
Thanks again!
( another detail to consider about the photo, the chat was not operative but the loading spinners were still running)
@andeeplus, thanks for the screenshot, it makes things clear now. The parent agent was set to Grok 4.7 High, and the subagent lines were labeled Grok 4.7 High Fast, even though they actually ran and were billed as Grok 4.7 High without Fast. So only the label in chat is wrong, and it does not affect usage. Your setting is not related here. I passed this to the team along with your Request ID and screenshot.
About the other similar reports, some of them really could be about the label, but not all of them. The most reliable way to check is the Usage page at https://cursor.com/dashboard. It shows which model each request was billed to. If someone sees Fast there too, that is a different case. In that case, it’s best to open a separate thread with the Request ID and Cursor version.
@luca_suanez, for the original case Explore subagent in Settings > Agents with Composer 2.5 and Fast turned off, it should work correctly now. If you still see composer-2.5-fast for subagents on the Usage page, please open a new thread with the Request ID and Cursor version, and we’ll look into it separately.
I’ll post here when there are updates about the label.
