Link blowing for fuses have some reliability problems - Suggest doing some processing of the signal and not just using it as a digital state:

Think - Wheatstone bridge, with one of the 4 elements being the poly link, and the bridge intentionally out of balance when the link has not been blown.

The output of the bridge feeds into a comparator.

When the link is blown, comparator output changes.

This type of design allows the blown link to still function if the link blows open cleanly, or only shifts in resistance value some.

Other reliability problems here are unique to the foundry, but the above method gets you around a lot of the problems with links not fully opening, or changing value (think particle contamination) after being blown or cut open.