We should make an additional documentation page, called "Example overview". In this page we list the examples (as bullet points). In each bullet point we explain what the user can learn by each example page.

Eg. from HK model they learn synchronous agent update. From COVID-19 they learn using arbitrary graphs and plotting on arbitrary graphs. etc.

We should be able to attach names to rules, so that normalization steps (and error messages?) can be better understood by users. For example:

normalize(@term(diff(x + y, x)))
 - @term(diff(x,x) + diff(y,x)) by sum rule in differentiation
 - @term(one(x) + diff(y, x)) by linear rule of differentiation
 - @term(1 + diff(y, x)) by multiplicative identity of a number
 - @term(1 + zero(x))