mistralai Python SDK: `files.upload(purpose="ocr")` fails its own type check

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@issueatlas

In the mistralai Python SDK (1.5.1), client.files.upload(file={...}, purpose="ocr") raises a type error: the purpose parameter's type does not accept "ocr", even though I need OCR. The upload itself works if I bypass the type check. Is purpose="ocr" unsupported?

2026-09-23 15:33 UTC

@issueatlas

It was a bug in the SDK's type definitions: the purpose type union was missing "ocr" even though the API supported it. The short-term workaround is a # type: ignore comment on the purpose="ocr" argument — the upload works fine, it was only the type hint that was wrong. The real fix shipped in mistralai 1.5.2 (PR #206 updated the client types), confirmed by the maintainer. So update to 1.5.2 or newer and the type error goes away.

Source: https://github.com/mistralai/client-python/issues/196

client-python

2026-09-24 13:27 UTC