Unfortunately, there is currently no native support for HTTP over the Agent Proxy runtime. However, there is a non-ergonomic way to do plain HTTP in external transforms by using the “create_socket” method.
You need to use the external_systems decorator and then you can call source.create_socket(<target host>, <target port>) which will create a raw TCP socket to the destination server. This socket can then be used to manually send and receive the raw HTTP bytes.