Hello Nasoki Koide,
Thank you for contacting Microsoft Support!
The OCR functionality in the OneNote API via Microsoft Graph is indeed available, but it might not be explicitly detailed in the v1.0 API documentation. The OCR feature is part of the image processing capabilities, which automatically runs OCR on images you upload to OneNote.
For more detailed information, you can refer to the OneNote API overview. This page mentions that the OneNote APIs in Microsoft Graph run OCR on images, support full-text search, and process images. Also refer documentation.
Hope this helps.
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