Deciding on the syntax and semantics myself and using AI to help implement my toy language has been very rewarding.

Mine is an Io and Rebol inspired language that uses SQlite and Luajit as a runtime.

.FizzBuzz : .run : [ n | if n % 15 = 0 'FizzBuzz'.say! .else if n % 3 = 0 'Fizz'.say! .else if n % 5 = 0 'Buzz'.say! .else n.say! ]

1.to 100 .each[ n | FizzBuzz.run n]