Selection of a distributed network service

A technology is described for selecting a distributed network service based at least in part on consistency, availability, and partition tolerance (CAP) metrics. An example method may include receiving a client request for a listing of distributed network services and associated CAP metrics that are within a range of at least one CAP specification included in the client request. In response to the client request, a directory service may be queried for a set of distributed network services having the CAP metrics that are within the range of the least one CAP specification included in the client request. A listing of distributed network services that includes the CAP metrics for the distributed network services may be generated from the set of distributed network services, and the listing of distributed network services and CAP metrics may be returned in response to the client request.