For a company selling intelligence, that's a pretty stupid way of labelling a new product.

exactly my thought too, go up with the version number! Some negative examples: Claude Sonnet 3.5 for Workstations, Claude Sonnet 3.5 XP, Claude Sonnet 3.5 Max Pro, Claude Sonnet 3.5 Elite, Claude Sonnet 3.5 Ultra

Because its a finetune of 3.5 optimized for the use case of computer use.

Its actually accurate and its not a 3.6.

The confusing choice they seem to have made is that "Claude 3.5 Sonnet" is a name, rather than 3.5 being a version. In their view, the model "version" is now `claude-3-5-sonnet-20241022` (and was previously `claude-3-5-sonnet-20240620`).

https://docs.anthropic.com/en/docs/about-claude/models

Maybe they notice 3.5 Sonnet has become a brand and pivot it away from a version

claude-3-5-sonnet-20241022

Well, by calling it 3.5, they are telling you that this is NOT the next-gen 4.0 that they presumably have in the works, and also not downplaying it by just calling it 3.6 (and anyways they are not advancing versions by 0.1 increments - it seems 3.5 was just meant to convey "half way from 3.0 to 4.0"). Maybe the architecture is unchanged, and this just reflects more pre and/or post-training?

Also, they still haven't released 3.5 Opus yet, but perhaps 3.5 Haiku is a distillation of that, indicating that it is close.

From a competitive POV, it makes sense that they respond to OpenAI's 4o and o1 without bumping the version to Claude 4.0, which presumably is what they will call their competitor to GPT-5, and probably not release until GPT-5 is out.

I'm a fan of Anthropic, and not of OpenAI, and I like the versioning and competitive comparisons. Sonnet 3.5 still best coder, better than o1, has to hurt, and a highly performant cheap Haiku 3.5 will hit OpenAI in the wallet.

Let's just say that the LLM companies still are learning how to do versioning in a customer friendly way.

Similar to OpenAI when they update their current models they just update the date, for example this new Claude 3.5 Sonnet is "claude-3-5-sonnet-20241022".

Just guessing here, but I think the name "sonnet" is the architecture, the number is the training structure / method, and the model date (not shown) is the data? So presumably with just better data they improved things significantly? Again, just a guess.

My guess is they didn't actually change the model, that's what the version number no change is conveying. They did some engineering around it to make it respond better, perhaps more resources or different prompts. Same cutoff date too.