How to convince ourselves that PROV facilitates interoperability

What we have:

• Tools that either produce or consume provenance.
• Cababilities that Tools perform.
  • c1: Reads prov
  • c2: Reads prov-o
  • c3: Shows trace
  • c4: Validates
  • ...

1) Each tool lists their own N capabilities:

• T_1: {c1},
• T_2: {c4}

2) Tools produce their provenance:

• out(T_1)
• out(T_2)

3) The interoperability between any two Tools, I_{s,t} is quantified by:

I_{1,2} = sum( T_1(out(T_2)): {yes(c1)}, 
               T_2(out(T_1)): {no(c1)} ) = 1 yes

Each tool is rated as "c/N" for c successful features performed on any provenance given.