  We introduce two methods for improving the performance of agents meeting for
the first time to accomplish a communicative task. The methods are: (1)
`message mutation' during the generation of the communication protocol; and (2)
random permutations of the communication channel. These proposals are tested
using a simple two-player game involving a `teacher' who generates a
communication protocol and sends a message, and a `student' who interprets the
message. After training multiple agents via self-play we analyse the
performance of these agents when they are matched with a stranger, i.e. their
zero-shot communication performance. We find that both message mutation and
channel permutation positively influence performance, and we discuss their
effects.
