Agility Ecommerce integrates with PayPal via Braintree APIs. Once a Braintree account is setup, there are four values required by Agility Ecommerce to process transactions via PayPal. These fields are MerchanID, Public Key, Private Key, and Tokenization Key. All four of these keys can be found/generated under Braintree's API Keys section.
Once you are in API Keys section you can generate new keys, disable or delete existing keys to revoke access.
Next step is to map the keys (omitted) in the screenshot above to a payment provider in Agility Ecommerce under Ecommerce > Ecommerce Settings > Payment Providers. Payment Provider is expecting the mapping of values in JSON format.
"MerchantID": "live merchant id",
"PublicKey": "live public key",
"PrivateKey": "live private key",
"TokenizationKey": "live tokenization key",
"MerchantID": "sandbox merchant id",
"PublicKey": "sandbox public key",
"PrivateKey": "sandbox private key",
"TokenizationKey": "sandbox tokenization key"
Your PayPal payment provider setup is now complete and it will look similar to the following screenshot.