Hi,
Thanks for reaching out to the Google Ads API Support.
You can check the daily operations usage for a developer token. Daily API usage limits are based on the number of API operations made per developer token.
In order to check the developer token access, sign in to your manager account and navigate to TOOLS & SETTINGS > SETUP > API Center. The API center is only available for MCC accounts and we can obtain a developer token for MCC accounts not for test manager accounts. Also, note that only the production manager account has the API center. I would suggest you refer to the Obtain a developer token and API Limits and Quotas documentation for detailed instructions.
Kindly note that each developer token is assigned an access level which controls the number of operations and requests that you can execute daily. Basic access level allows the developer token to execute up to 15,000 operations per day, suggesting you fill out the basic access application. In order to avoid API limits then please fill out the standard access application form for unlimited Google Ads API operations. I would suggest you refer to this Access Levels and Permissible Use guide and help center article to know more about how to Manage users and access levels for your manager account.
Thanks
Google Ads API team.