Hello,
Agisoft Cloud can be accessed via Python API with Metashape.CloudClient() class, however the available options are limited. It is available to process the project in the cloud, monitor the processing status and download results, but it is not available to execute custom scripts in the cloud.
Whether your pipeline includes Metashape processing tasks and custom post processing, we suggest you combine the cloud and local processing. For example you can send the images for alignment to the cloud, when alignment is completed you can download the processed project and perform custom post processing locally before sending the next task to the cloud.