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Cursor Composer 2 is just Kimi K2.5 with RL

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Re: Cursor Composer 2 is just Kimi K2.5 with RL

#91
post #9

A hyped startup providing zero added value, burning investor money only to repackage somebody else's work? That's new... /s

Incompetently repackaging. They started with VSCode so nearly all the work was already done, but still managed to make it leak memory like it's infinite. The power of AI slop! Their product is an anti-advertisement for the core concept of itself, which is kind of impressive.

Re: Cursor Composer 2 is just Kimi K2.5 with RL

#92

Cursor is mostly an IDE / coding-agent harness company. So it probably makes sense for them not to train their own base model, but instead license something like Kimi and fine-tune it for their own harness and workflows. Their moat looks pretty thin. A VSCode fork with an open-source LLM fork on top. In the fast-moving coding-agent market, it’s not obvious they keep their massive valuation forever.

> Their moat looks pretty thin. Their value is in the data they've collected and are collecting. Usage, acceptance rate, and all the connected signals. Plus having a large userbase where they can A / B test any finetune they create.

I hope for their sake they're using real metrics internally, and not whatever nonsense they're using to calculate stuff like "% written by LLM" in their dashboard, because that's... very wrong.

Re: Cursor Composer 2 is just Kimi K2.5 with RL

#93
"Just" Kimi K2.5 with RL—people really misunderstand how difficult it is to achieve these reults with RL. Cursor's research team is highly respected within the industry, and what they've done is quite impressive.

Before people go jumping to conclusions about model theft, it's worth considering the possibility that they did reach an agreement with Moonshot which their researchers were not aware of. That would certainly explain the deleted tweets. Until Moonshot makes an official statement, I'm not particularly concerned.

Re: Cursor Composer 2 is just Kimi K2.5 with RL

#94
What does this mean, that you can take Kimi and RL finetune it a little more and blow the big AI shops out of the water?

Would this have been extensively fine tuned, beyond what Anthropic/OAI would do themselves?

I guess this is Cursor's own benchmark, so you can finetune on your own dataset and get better results on your own specific tasks I guess.

Re: Cursor Composer 2 is just Kimi K2.5 with RL

#96
post #40

A question. I’m due for a yearly Cursor subscription renewal, how does the credit limit look like? Currently I’ve not hit any of the limits despite using it quite rigorously, I wonder if this will change with a renewal?

But you have to buy into it right? If you don't have a limit then what did your contract look like?

I signed up last year when the limits were a lot more generous.

Re: Cursor Composer 2 is just Kimi K2.5 with RL

#100
They’re pretty upfront in their release post that they took an open source model and improved it with their own coding data. They mention “continued pretraining” (on top of the base model) and RL. Cursor never claimed to have done a full pretraining run.

More to the point, beating Opus 4.6 at coding and coming within striking distance of gpt-5.4 is impressive! The benchmarks outperform raw Kimi K2.5.

It’s particularly impressive given larger labs like Meta are struggling to catch up to OpenAI/Anthropic.

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