diff --git a/home-modules/lib.nix b/home-modules/lib.nix
index 89513c2..9baf298 100644
--- a/home-modules/lib.nix
+++ b/home-modules/lib.nix
@@ -26,6 +26,12 @@ let
     rev = "4ae5198fb82fe28d7b452796152f2b1745051c77";
     hash = "sha256-NvDd3BSVeS10kYupLxo27VlKeeHPHrxyTb8EdVqrtQw=";
   };
+  inthAgentSkills = pkgs.fetchFromGitHub {
+    owner = "inthhq";
+    repo = "agent-skills";
+    rev = "ffcbc99bc3d8a72deb5659c18a2ccdfaf416fc1c";
+    hash = "sha256-as2+FYIohxwcwFiaucJ6heFtZmDlA4l1jVXUU9wh5SQ=";
+  };
   betterbird = pkgs.stdenv.mkDerivation rec {
     pname = "betterbird";
     version = "140.10.0esr-bb21";
@@ -482,6 +488,7 @@ in
       email
       ghosttyZellijStartup
       greptileSkills
+      inthAgentSkills
       name
       nasaApodWallpaper
       signalStartup
diff --git a/home-modules/opencode.nix b/home-modules/opencode.nix
index ce2adbd..93dfd44 100644
--- a/home-modules/opencode.nix
+++ b/home-modules/opencode.nix
@@ -4,6 +4,23 @@
   home.file.".agents/skills/check-pr".source = "${homeLib.greptileSkills}/check-pr";
   home.file.".agents/skills/greploop".source = "${homeLib.greptileSkills}/greploop";
   home.file.".agents/skills/fuzz/SKILL.md".text = builtins.readFile ./skills/fuzz.md;
+  home.file.".agents/skills/ecmascript-modernization".source =
+    "${homeLib.inthAgentSkills}/ecmascript-modernization";
+
+  home.file.".config/opencode/commands/ecmascript-modernization.md".text = ''
+    ---
+    description: Modernize JavaScript or TypeScript to ECMAScript APIs
+    agent: build
+    ---
+
+    First load the `ecmascript-modernization` skill with the skill tool.
+
+    Use it for this JavaScript or TypeScript ECMAScript modernization request:
+
+    $ARGUMENTS
+
+    Treat the arguments as an ECMAScript edition, file pattern, or task scope. If no arguments are provided, inspect the project for safe modernization opportunities. Before editing, check the runtime baseline, TypeScript version, and `tsconfig.json`.
+  '';
 
   home.file.".config/opencode/opencode.json".text = builtins.toJSON {
     "$schema" = "https://opencode.ai/config.json";