Apply suggestions from code review

Co-authored-by: Jim Fehrle <[email protected]>

Author: mattam82

doc/sphinx/addendum/type-classes.rst

@@ -327,7 +327,7 @@ Command summary
    When record syntax is used, this command also supports the
    :attr:`projections(primitive)` :term:`attribute`.
 
-   .. attr:: mode = @string
+   .. attr:: mode = "{+ {| + | ! | - } }"
       :name: mode
 
       Sets the mode of resolution for queries on the class.
@@ -575,7 +575,7 @@ Settings
 
 .. _TypeclassesDefaultMode:
 
-.. opt:: Typeclasses Default Mode {| "+" | "-" | "!" }.
+.. opt:: Typeclasses Default Mode {| "+" | "-" | "!" }
 
    Sets the default mode declaration associated with a :cmd:`Class` or :cmd:`Existing Class`
    declaration. It is set by default to "-", i.e. doing no mode filtering