The Safe portal uses the classic API Key approach. It will be for every operation you make after the login.
Keys expire. We recommend starting a new session if a few minutes have passed since your last operation. Operations renew keys for a brief period.
Before you log in, you must get the safe ID. This ID can be easily seen in the Defender Max Panel when editing a Safe. As described in the following image:

If you don’t have it, there is an unsecured endpoint called ‘getSafes’ that will provide you with the names and IDs of each safe. As shown in the example

After logging in successfully, you can start using the endpoints for file management.