There isn't a single, universally accepted specification for s-expressions specifically as a data transfer format. But like I said: there's EDN - primarily use

There isn't a single, universally accepted specification for s-expressions specifically as a data transfer format. But like I said: there's EDN - primarily used for configuration files, data serialization/deserialization between systems, inter-process communication And there's Transit - Ideal for scenarios requiring fast data transport over networks, such as web services and APIs, it supports both JSON and MessagePack encodings.