Magento 2 add custom rest api endpoints
{base_url}/rest/default/V1/mma/categories
{base_url}/rest/default/V1/mma/braintree/token
{base_url}/rest/default/V1/mma/me/vault/items
{base_url}/rest/default/V1/mma/me/vault/nonce
composer require mma/customapi
php bin/magento setup:upgrade
php bin/magento cache:clean
Tested on Magento Commerce 2.2.5