diff --git a/lib/modules.nix b/lib/modules.nix
index 4dc8c663b2fe..5821aeab20c7 100644
--- a/lib/modules.nix
+++ b/lib/modules.nix
@@ -1146,14 +1146,11 @@ let
     use = id;
   };
 
-  /* Transitional version of mkAliasOptionModule that uses MD docs. */
-  mkAliasOptionModuleMD = from: to: doRename {
-    inherit from to;
-    visible = true;
-    warn = false;
-    use = id;
-    markdown = true;
-  };
+  /* Transitional version of mkAliasOptionModule that uses MD docs.
+
+     This function is no longer necessary and merely an alias of `mkAliasOptionModule`.
+  */
+  mkAliasOptionModuleMD = mkAliasOptionModule;
 
   /* mkDerivedConfig : Option a -> (a -> Definition b) -> Definition b
 
@@ -1175,7 +1172,7 @@ let
       (opt.highestPrio or defaultOverridePriority)
       (f opt.value);
 
-  doRename = { from, to, visible, warn, use, withPriority ? true, markdown ? false }:
+  doRename = { from, to, visible, warn, use, withPriority ? true }:
     { config, options, ... }:
     let
       fromOpt = getAttrFromPath from options;
@@ -1186,9 +1183,7 @@ let
     {
       options = setAttrByPath from (mkOption {
         inherit visible;
-        description = if markdown
-          then lib.mdDoc "Alias of {option}`${showOption to}`."
-          else "Alias of <option>${showOption to}</option>.";
+        description = "Alias of {option}`${showOption to}`.";
         apply = x: use (toOf config);
       } // optionalAttrs (toType != null) {
         type = toType;
diff --git a/lib/options.nix b/lib/options.nix
index 11a3984aa47e..c42bc1e6c67e 100644
--- a/lib/options.nix
+++ b/lib/options.nix
@@ -100,10 +100,7 @@ rec {
     name: mkOption {
     default = false;
     example = true;
-    description =
-      if name ? _type && name._type == "mdDoc"
-      then lib.mdDoc "Whether to enable ${name.text}."
-      else "Whether to enable ${name}.";
+    description = "Whether to enable ${name}.";
     type = lib.types.bool;
   };
 
@@ -185,10 +182,10 @@ rec {
           (if isList example then "pkgs." + concatStringsSep "." example else example);
       });
 
-  /* Like mkPackageOption, but emit an mdDoc description instead of DocBook. */
-  mkPackageOptionMD = pkgs: name: extra:
-    let option = mkPackageOption pkgs name extra;
-    in option // { description = lib.mdDoc option.description; };
+  /* Alias of mkPackageOption. Previously used to create options with markdown
+     documentation, which is no longer required.
+  */
+  mkPackageOptionMD = mkPackageOption;
 
   /* This option accepts anything, but it does not produce any result.
 
@@ -347,11 +344,9 @@ rec {
   literalExample = lib.warn "literalExample is deprecated, use literalExpression instead, or use literalMD for a non-Nix description." literalExpression;
 
   /* Transition marker for documentation that's already migrated to markdown
-     syntax.
+     syntax. This is a no-op and no longer needed.
   */
-  mdDoc = text:
-    if ! isString text then throw "mdDoc expects a string."
-    else { _type = "mdDoc"; inherit text; };
+  mdDoc = lib.id;
 
   /* For use in the `defaultText` and `example` option attributes. Causes the
      given MD text to be inserted verbatim in the documentation, for when