The short answer
You drew it. Every expressive mark in the final image came from your hand and your judgement.
Tools that change what you drew are fine. Tools that make new content for you are not.
The test that usually settles it
Ask: did this tool generate visual content, or did it change visual content I made?
Rotating, scaling, colour-correcting, blurring, sharpening, masking, and brush stabilisation all take your marks and change them. That's editing.
A background, texture, character, line, or fill that didn't exist until a model made it is generation, and it isn't allowed.
Edge cases
Reference material. Looking at photos, other art, or anything else while you draw is normal. Reference isn't the same as source material.
A generated image used as a starting composition. Not allowed, even if you redraw over all of it. The composition counts as expressive content.
Machine-learning tools that remove rather than create, like background removal, denoising, or non-generative upscaling. These are genuinely unclear, so BHFH lists them as under review. Disclose them.
A collaborator. If another person drew part of it, say so in your listing.
When you are not sure
Mention it in your listing notes. "I used X for Y" is a normal thing to write, and it's much better than us finding out later.