1. A method, comprising: receiving, by a first network device in an application programming interface (API) management layer of a service provider network, a token request from an application on a user device; monitoring, by the first network device, a group of proxy servers in the API management layer to determine workloads of the group of proxy servers in the API management layer; generating, in response to the token request, a token that includes a time-stamp and a server identifier, the server identifier indicating a particular proxy server, of the group of proxy servers and the server identifier being assigned to balance the workloads among the group of proxy servers; sending, by the first network device and to the application, the token; receiving, from the application and by a second network device in the API management layer, an API call that includes the token; validating, by the second network device, the token; routing, by the second network device, the API call to the particular proxy server indicated by the token in response to successfully validating the token; and providing, to the application, a bypass uniform resource locator (URL), to bypass the API management layer, for one or more types of designated API calls, wherein use of the bypass URL requires separate validation using the token.