Over 7 years ago a change has been [introduced to add an auto option on the content-type parameter](https://github.com/oracle/oci-cli/blame/b4f6cd3f6c491a506d1eeeacb3c6d99ea9880b58/services/object_storage/src/oci_cli_object_storage/objectstorage_cli_extended.py#L648) but this has so far not been added to the docs that show up at https://docs.oracle.com/en-us/iaas/tools/oci-cli/latest/oci_cli_docs/cmdref/os/object/put.html#cmdoption-content-type I'll add a pull request with a proposed change to amend the doc.