It’s more akin to a SaaS company releasing a compiled binary that usually runs on their server. Better than nothing, but not exactly in the spirit of open source.
This doesn’t seem like a pedantic distinction, but I suppose it’s up to the community to agree or disagree.
A compiled binary is a bad metaphor because it gives the implication that Mistral-7B is an as-is WYSIWIG project that's not easily modifiable. In contrast, there have been a bunch of new powerful new models created by modifying or finetuning Mistral-7B such as Zephyr-7B: https://huggingface.co/HuggingFaceH4/zephyr-7b-beta
The better analogy to Mistral-7B is something like modding Minecraft or Skyrim: although those games are closed source themselves, it has enabled innovations which helps the open-source community directly.
It would be nice to have fully open-source methodologies but lacking them isn't an inherent disqualifier.
If you want to reproduce the training pipeline, you couldn't do that even if you wanted to because you don't have access to thousands of A100s.
"Source code is defined as the preferred form of the program for making changes in. Thus, whatever form a developer changes to develop the program is the source code of that developer's version."
According to the Open Source Definition:
"The source code must be the preferred form in which a programmer would modify the program. Deliberately obfuscated source code is not allowed. Intermediate forms such as the output of a preprocessor or translator are not allowed."
LLM models are usually modified by changing the model weights directly, instead of retraining the model from scratch. LLM weights are poorly understood, but this is an unavoidable side effect of the development methodology, not deliberate obfuscation. "Intermediate" implies a form must undergo further processing before it can be used, but LLM weights are typically used directly. LLMs did not exist when these definitions were written, so they aren't a perfect fit for the terminology used, but there's a reasonable argument to be made that LLM weights can qualify as "source code".
They're understood based on knowing the training process though, and a developer working on them would want to have the option of doing a partial or full retraining where warranted.