A system and method are presented for invoking integration actions in a unified collaboration system. A client communicates with a bridging web server through a ReST. The bridging web server comprises a cloud service which facilitates communication with integration servers, which may be located on-premises. In an embodiment, the integration server(s) host a number of plugins which are capable of implementing integration actions. The bridging web server decides which action implementation is the best one to service a request. The implementation may be based on prior configuration. Routing decisions on the bridging web server may be automatically selected based on prior configuration.