How can I get system user token of another facebook business to manage their audiences?

Question

I am working to build an application which would be able to create custom audiences for many of our clients for facebook ads. I came to know that the most suitable access token for this purpose is system user token (correct me if I am wrong). To get regular user access tokens, we can make a user go through the traditional oAuth flow, I am looking for something similar to get system user access token. How can I get it for any of my clients? Thanks

Answer 1

You must create your system users in the Business Manager of your company:

https://business.facebook.com/settings/system-users?business_id=<YOUR_BUSINESS_ID>

Once you create a system user, you can generate a token for him associated with a given app.

Meanwhile, on your business settings (as stated in the docs) you can request access to an ad_account.

Request Access to an Ad Account: If you request access to an ad account in Business Manager, the admin of that Business Manager can grant you permission to work on it.

Once your client gives your Business permission to work with one or more of their ad_accounts, those ad_accounts will appear in your Business Manager. (menu on the left).

At that point, when checking the profile of your system users, you can click on assign assets to give the system user access to pages and ad_accounts.

The token you generated for the pair [system_user,app_id] does not need to be reissued to reflect the addition of assets to which the system_user has access.