moth/doc/tokens.md

Tokens

Tokens are good for a single point in a single category. They are formed by prepending the category and a colon to the bubblebabble digest of 3 random octets. A token for the "merfing" category might look like this:

merfing:xunap-motex

Entropy

3 octets provides 24 bits of entropy. This gives 16777216 possible tokens in each category. The longest contest yet run lasted 24 hours, which would give 2^24/24/60 = 11650 tokens per category per minute. I think this is a large enough pool to discourage brute-force attacks. Assuming /dev/urandom is as good as is claimed, brute-force would be the only way to attack it.