frequent 500 errors that reproduce, without any apparent resason

### Description of the bug:


In some of my use cases, I have very frequent 500 errors.
I'm retrying them, but some are persistent.

Here's an example `GenerateContentParameters`

https://gist.github.com/uriva/ec104cbf926ad142036490460ce8c2ad


### Actual vs expected behavior:


A good error message.

### Any other information you'd like to share?


_No response_