A service agent provides an interface for the actions that a client application needs to perform against a server. The service agent selects an appropriate service implementation based on configuration information. The service implementation is associated with a particular service version or source. A number of service implementations are available to the service agent. The service agent also creates a cache service instance that is compatible with the service instance. The client application makes data requests through the service agent. The cache service retrieves requested data from a local storage or from a selected service, if the data is not available locally. The cache service stores an expiration value with the data in the cache. The expiration value is retrieved when data is requested from the cache. The cache data is returned only if the expiration value has not exceeded an expiration policy.