Ichabod’s horseman, This wouldn’t appease. A hard-headed helper, Shell of shell, to your seed. It’s made to absorb, Cracks it tries to impede. You’ll be this at the end, If you keep up bad deeds.

I border the blue or glide without strain, the same simple word for land or for lane.

Add an OR to the end, and I’m like a detective. Add Gadget after that - go, go, get Penny to save the day. Left alone, I look at things to find clues; another word for the work done.

Kids do me on sidewalks, old scratched CDs do me by accident. One makes you smile, the other makes you annoyed.

I rhyme like this, and I'm usually quite keen. I'm structured in order, yet restart in between.