Methods, systems, and apparatus, including computer programs encoded on computer storage media, for a dynamic api, includes receiving a first message in a first format from a client, the first format being specified for the client, the first message including information sufficient to cause a target service to execute an operation. The method includes identifying, using the API message, the target service. The method includes determining based of the target, a second format. The method includes generating a second message in the second format prescribed by the target service using the first message, the second message including information sufficient to cause the target service to execute the operation. The method also includes sending the second message to the target service over the network connector.