Originally Posted by Gordon Scott
This has been puzzling me a bit ... it's not a scale with which I'm familiar, but I would have considered it to contain the natural fourth and the flat fifth, not the sharp 4th, so G, A, B, C, Db, E, F#.
My personal view is that it's not a Lydian variant, which contains the sharp 4th, not the natural fourth.

I'm no expert, though, so maybe AI outranks me here?

You are more right than you are wrong. Guitarhacker and David addressed this above.

Let me add, you asked AI for a "G lydian b5 scale", so you biased it to refer to a diminised scale with the b5th instead of the augmented scale with the #4th. The scale notes are enharmonically equivalent in this case. If you were to have asked for a G lydian scale - you would have certainly seen a augmented scale with the #4th reported. The two scales are exactly the same notes, but yes, they do have different musical roles depending on context. Keep asking questions, you are on the right course.

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