That's a good point about obfuscation being unnecessary -- I've updated my comment to address it. I was stuck on the fact that you can exploit any rank in advance, and had a vague feeling that you could turn this into a bot that can exploit ranks on the fly. This feeling didn't hold up well under inspection. With regards to your other concerns:

You are encouraged to discuss strategies for achieving mutual cooperation in the comments thread.

- the judge

I considered holding back much of my own strategy, until I realized that there's really no such thing as an optimal bot in this contest. For example, common sense says that you should exploit CooperateBot for free utility. However, if you expect to face more JusticeBots than CooperateBots then you should pass up that utility for the opportunity to exploit the JusticeBots.

This problem is a social engineering problem by construction. The game won't go to the bot with the cleverest code, it will go to the bot that best guesses the composition of the playing field.