diff --git a/tools/ui/.prettierignore b/tools/ui/.prettierignore
index 635cf99c7e..ba47fbe165 100644
--- a/tools/ui/.prettierignore
+++ b/tools/ui/.prettierignore
@@ -19,3 +19,7 @@ test-results
 
 # Vendored third party sources, kept byte identical to upstream
 src/lib/vendors/
+
+# Agent skills installed from upstream, kept as installed
+.agents/
+skills-lock.json