Fix bottom text of the comment

public/scripts/instruct-mode.js

@@ -519,6 +519,7 @@ function selectMatchingContextTemplate(name) {
  * Replaces instruct mode macros in the given input string.
  * @param {string} input Input string.
  * @param {Object<string, *>} env - Map of macro names to the values they'll be substituted with. If the param
+ * values are functions, those functions will be called and their return values are used.
  * @returns {string} String with macros replaced.
  */
 export function replaceInstructMacros(input, env) {