Cursor AI releases Composer 2.5, its most powerful model to date, with gains on long-running tasks and complex instructions after allocating 85 percent of compute to additional training and reinforcement learning
Company-wide internal testing for two days went unnoticed by users.
#23Sasha Rush@SRUSH_NLPBeen working on text feedback / OPSD in Composer. Really interesting space, and a much more to be explored.
@eliebakouch Unfortunately can’t give a precise answer. Both were scaled significantly.
elie@eliebakouch@srush_nlp really cool work congrats to the team. if you can answer, do you have rough estimate on how the compute was allocated between RL and continual pt in composer 2 -> 2.5?
#23Sasha Rush@SRUSH_NLPBeen working on text feedback / OPSD in Composer. Really interesting space, and much more to be explored.
#68clem 🤗@CLEMENTDELANGUEVery cool to see Cursor doubling down on training great models. In my opinion, ultimately all serious companies in AI will want to train models themselves, based on open-source instead of outsourcing AI to others via APIs!
Cursor@cursor_aiIntroducing Composer 2.5, our most powerful model yet. It's more intelligent, better at sustained work on long-running tasks, and more reliable at following complex instructions. For the next week, we’re doubling the included usage of the model.
#76Elon Musk@ELONMUSKTry it out!
(Partially trained on Colossus 2)
Cursor@cursor_aiIntroducing Composer 2.5, our most powerful model yet. It's more intelligent, better at sustained work on long-running tasks, and more reliable at following complex instructions. For the next week, we’re doubling the included usage of the model.
#167Emad@EMOSTAQUEThis is such an interesting chart layout, like it a lot!
Congrats to @cursor_ai team on the 2.5 launch 🚀
#357Boris Power@BORISMPOWERGreat work - exciting to see you training a very powerful coding model!
Cursor@cursor_aiIntroducing Composer 2.5, our most powerful model yet. It's more intelligent, better at sustained work on long-running tasks, and more reliable at following complex instructions. For the next week, we’re doubling the included usage of the model.
#506Michael Truell@MNTRUELLComposer 2.5 is a significant step up from Composer 2.
This is the very start of our work with SpaceXAI. Hope to have more improvements out soon.
Cursor@cursor_aiIntroducing Composer 2.5, our most powerful model yet. It's more intelligent, better at sustained work on long-running tasks, and more reliable at following complex instructions. For the next week, we’re doubling the included usage of the model.
#583Niklas Muennighoff@MUENNIGHOFFComposer 2.5 sits on the Pareto frontier
Cursor@cursor_aiIntroducing Composer 2.5, our most powerful model yet. It's more intelligent, better at sustained work on long-running tasks, and more reliable at following complex instructions. For the next week, we’re doubling the included usage of the model.
#612Ravid Shwartz Ziv@ZIV_RAVIDSelf distillation everywhere 🥳
Cursor@cursor_aiIntroducing Composer 2.5, our most powerful model yet. It's more intelligent, better at sustained work on long-running tasks, and more reliable at following complex instructions. For the next week, we’re doubling the included usage of the model.
#694Dan Fu@REALDANFU🎼2⃣5⃣
Together AI@togethercomputeCongrats to the @cursor_ai team on Composer 2.5 — a huge milestone for agentic coding models. Together AI, the AI Native Cloud, is proud to partner on this launch. Composer 2.5 is pushing the frontier for coding agents and turning heads for its speed and quality. Excited to keep building with the Cursor team!
#716elie@ELIEBAKOUCH@srush_nlp really cool work congrats to the team. if you can answer, do you have rough estimate on how the compute was allocated between RL and continual pt in composer 2 -> 2.5?
Sasha Rush@srush_nlpBeen working on text feedback / OPSD in Composer. Really interesting space, and a much more to be explored.
#716elie@ELIEBAKOUCHcursor is at frontier scale, both in terms of performance and compute
if composer 2.5's budget was put into a pre-train: ~6.3T total, 200B active trained on ~56T tokens
if composer 3 allocates 50% of the budget to pre-training: ~500B active, 15.3T total trained on 135T tokens.
assumptions are a lower bound: 35% MFU, FP8, ~3-4% sparsity like K2, H100 efficiency. model/token allocation is the mean between K2+K2.5 data point and Inclusion AI compute optimal rules for MoE
really impressed by the progression between composer 2 and composer 2.5
Cursor@cursor_aiIntroducing Composer 2.5, our most powerful model yet. It's more intelligent, better at sustained work on long-running tasks, and more reliable at following complex instructions. For the next week, we’re doubling the included usage of the model.
#716elie@ELIEBAKOUCH> if composer 3 allocates 50% of the budget to pre-training: ~500B active, 15.3T total trained on 135T tokens.
i meant pre/mid/continual training here (whatever is not RL), and also put 10% estimation in the attached picture
elie@eliebakouchcursor is at frontier scale, both in terms of performance and compute if composer 2.5's budget was put into a pre-train: ~6.3T total, 200B active trained on ~56T tokens if composer 3 allocates 50% of the budget to pre-training: ~500B active, 15.3T total trained on 135T tokens. assumptions are a lower bound: 35% MFU, FP8, ~3-4% sparsity like K2, H100 efficiency. model/token allocation is the mean between K2+K2.5 data point and Inclusion AI compute optimal rules for MoE really impressed by the progression between composer 2 and composer 2.5
@ericzakariasson looks good
eric zakariasson@ericzakariassoncomposer 1 was fast composer 2 was fast and intelligent composer N:
#978Jacob Jackson@JBFJAOur new model is out. It stacks up nicely against the frontier!
Cursor@cursor_aiIntroducing Composer 2.5, our most powerful model yet. It's more intelligent, better at sustained work on long-running tasks, and more reliable at following complex instructions. For the next week, we’re doubling the included usage of the model.
#980Lisan al Gaib@SCALING01yeah that's pretty good
xAI might be able to cook with Cursor data + 10T model
Cursor@cursor_aiIntroducing Composer 2.5, our most powerful model yet. It's more intelligent, better at sustained work on long-running tasks, and more reliable at following complex instructions. For the next week, we’re doubling the included usage of the model.
#1086Ashvin Nair@ASHVINAIRWe just trained another really really good model, please try it! Frontier intelligence + very fast
#1245Alex Volkov@ALTRYNENew Composer from Cursor team! Great to see their ack. to the Kimi base + how much they moved the model forward!
This isn't the one they are training on XAI Colossus, that one is coming and would likely slap hard!
Cursor@cursor_aiIntroducing Composer 2.5, our most powerful model yet. It's more intelligent, better at sustained work on long-running tasks, and more reliable at following complex instructions. For the next week, we’re doubling the included usage of the model.
#1284Kevin Frans@KVFRANSWe used a pretty cool "RL with text feedback" formulation to train this one (see blog post for some details). As RL tasks get longer in horizon, I think it's a ripe time to think about ways we can extract signals that avoid the variance explosion.
Cursor@cursor_aiIntroducing Composer 2.5, our most powerful model yet. It's more intelligent, better at sustained work on long-running tasks, and more reliable at following complex instructions. For the next week, we’re doubling the included usage of the model.
#1318Sam Whitmore@SJWHITMOREcomposer 2.5 is really really great. I had it on last week for some testing, forgot that it was on, & totally didn’t realize I wasn’t on gpt 5.5 (my usual) for a while. the team did a fantastic job!!
Cursor@cursor_aiIntroducing Composer 2.5, our most powerful model yet. It's more intelligent, better at sustained work on long-running tasks, and more reliable at following complex instructions. For the next week, we’re doubling the included usage of the model.
@mntruell Congrats!
Michael Truell@mntruellComposer 2.5 is a significant step up from Composer 2. This is the very start of our work with SpaceXAI. Hope to have more improvements out soon.
#1496Chubby♨️@KIMMONISMUSIntelligence too cheap to meter. This is the real deal. Composer 2.5 is an efficiency-beast
Chubby♨️@kimmonismusHuge, did NOT expect that release. Evals looks very solid, significant jump compared to composer 2! But: it’s 10x more efficient than the competition. Looks really exciting. Need to try it out
#1496Chubby♨️@KIMMONISMUSHuge, did NOT expect that release. Evals looks very solid, significant jump compared to composer 2!
But: it’s 10x more efficient than the competition. Looks really exciting. Need to try it out
Cursor@cursor_aiIntroducing Composer 2.5, our most powerful model yet. It's more intelligent, better at sustained work on long-running tasks, and more reliable at following complex instructions. For the next week, we’re doubling the included usage of the model.
#1733Ryo Lu@RYOLU_frontier smart extremely efficient Composer 2.5 is here
Cursor@cursor_aiIntroducing Composer 2.5, our most powerful model yet. It's more intelligent, better at sustained work on long-running tasks, and more reliable at following complex instructions. For the next week, we’re doubling the included usage of the model.
#1749Sualeh Asif@SUALEHASIF996We've gotten really really good at RL. Composer 2.5 is fighting well-above its weight class.
Very excited for the next release as we scale model sizes and FLOPs with @SpaceXAI!
Cursor@cursor_aiIntroducing Composer 2.5, our most powerful model yet. It's more intelligent, better at sustained work on long-running tasks, and more reliable at following complex instructions. For the next week, we’re doubling the included usage of the model.
@ericzakariasson Fat slow and genius
eric zakariasson@ericzakariassoncomposer 1 was fast composer 2 was fast and intelligent composer N:
#1965eric zakariasson@ERICZAKARIASSONcomposer 1 was fast composer 2 was fast and intelligent composer N:
Cursor@cursor_aiIntroducing Composer 2.5, our most powerful model yet. It's more intelligent, better at sustained work on long-running tasks, and more reliable at following complex instructions. For the next week, we’re doubling the included usage of the model.
