With the Content API, you can upload images to the Mailjet image gallery, making them available in the user interface (UI). You can also manage or update the images that you have uploaded. You can also retrieve the URLs of images in order to add them to your templates.
You can control whether an image can be edited by setting its status in the Status field. When the status is set to locked, edits are prevented. Conversely, when the status is set to open, the image can be modified. The Status field is required when uploading an image.