What would need to be true for AI to translate a legal contract to a smart contract?

Background:  There is an advent of many business services being implemented as API's such as HR, payments, open banking, loyalty programs, shipping, etc.   These are important to the business but not core differentiators.  They are just slightly different enough in each context that you can't just copy and paste.  In the case of legal contracts, there are many common components but the entire contract will have variation.  It would be powerful to digitize these contracts so it can be much easier for business-to-business interaction and partnership.  My best representation of a digital contract today is the Ethereum smart contract concept.

What would need to be true for AI to translate and digitize a contract?