How should I fasten my shed rafters together at the peak?
First I have a barn that is very very similar - basically exactly the same, but I just enclosed the overhang section.
So I would suggest something similar to the picture below - you can google &quot;roof truss plate&quot;.  (obviously not a perfect example as that top center hole is not needed... this is not a great example, just the shape of the plates I have used before)
There are simpson ties that you can use shaped like this.   Whats the &quot;bottom&quot;?   I greatly suggest that you block each rafter connection a few inches below - small 2x6.   This will keep uneven loads or winds from pushing one side vs another.
You will also need to rows of blocking on each side.   This will not only help secure the sheathing for the roof but are structural against lateral rafter movement.