I'm crystal clear

Is my skin glass?
I can't tell
Everyone can see through me
Right through my shell

My eyes don't have X-ray vision
Even the specs never work
People know me in and out
Like their favorite shirt

I don't see anything
I'm a rotten tomato
Some people see good
But then, do they really know

My skin is glass
My bones are crystal
My heart is the billboard
That shows all