Create detailed explanation of formulas on website

There are 4 location on our website that query a database and display content. I want a programmer to create documentations for each instance that explains in good detail how the query works. I want to know what criteria it looks at, how it prioritizes it, how is sorts it, where I would need to go to edit the parameters to change the results, etc. The site is built on WordPress and most of the query is created using the existing WP search/query system.