1M context is amazing, but even after 100k tokens Gemini 2.5 Pro is usually incapable of consistently reproducing 300 LOC file without changing something in process. And it actually take a lot of effort to make sure it do not touch files it not suppose to.
With Gemini I have found some weird issues with code gen that are presumably temperature related. Sometimes it will emit large block of code with a single underscore where it should be a dash or some similar very close match that would make sense as a global decision but is triggered for only that one instance.
like code containing the same identifier.
Not to mention sneakily functions back in after being told to remove them because they are defined elsewhere. Had a spell where it was reliably a two prompt process for any change, 1) do the actual thing, 2) remove A,B and C which you have reintroduced again.I have had some very weird issues with Gemini 2.5 Pro where during a longer session it eventually becomes completely confused and starts giving me the response to the previous prompt instead of the current one. I absolutely would not trust it to handle larger amounts of data or information correctly.
Exactly, 1M context tokens is marketing, relatively little training was done at that input size.