diff --git a/.github/workflows/validate_skill.yml b/.github/workflows/validate_skill.yml
index b1dd8a50..d4598f12 100644
--- a/.github/workflows/validate_skill.yml
+++ b/.github/workflows/validate_skill.yml
@@ -14,16 +14,37 @@ jobs:
     steps:
       - uses: actions/checkout@v6
       - uses: actions/setup-python@v6
+        with:
+          python-version: "3.x"
+          cache: "pip"
+      - name: Install dependencies
+        run: |
+          python -m pip install --upgrade pip
+          pip install PyYAML
       - name: Validate SKILL.md files
         env:
-          BASE_SHA: ${{ github.event.pull_request.base.sha || github.event.before }}
           HEAD_SHA: ${{ github.sha }}
+          EVENT_NAME: ${{ github.event_name }}
+          DEFAULT_BRANCH: ${{ github.event.repository.default_branch }}
+          PR_BASE_REF: ${{ github.event.pull_request.base.ref }}
         run: |
           set -euo pipefail
-          echo "Base: $BASE_SHA"
+
+          HEAD_SHA="${HEAD_SHA}"
+
+          if [ "${EVENT_NAME}" = "pull_request" ]; then
+            BASE_BRANCH="${PR_BASE_REF}"
+          else
+            BASE_BRANCH="${DEFAULT_BRANCH}"
+          fi
+
+          echo "Base branch: $BASE_BRANCH"
           echo "Head: $HEAD_SHA"
 
-          DIFF=$(git diff --name-status "$BASE_SHA" "$HEAD_SHA" -- 'skills/*/SKILL.md' || true)
+          git fetch --no-tags origin "${BASE_BRANCH}:refs/remotes/origin/${BASE_BRANCH}"
+          BASE=$(git merge-base "refs/remotes/origin/${BASE_BRANCH}" "$HEAD_SHA")
+
+          DIFF=$(git diff --name-status "$BASE" "$HEAD_SHA" -- 'skills/*/SKILL.md' || true)
 
           if [ -z "$DIFF" ]; then
             exit 0
@@ -68,36 +89,38 @@ jobs:
           fi
 
           # Validate skills that were added or modified
-          CHANGED_FILES=$(echo "$DIFF" | awk '
+          CHANGED_FOLDERS=$(echo "$DIFF" | awk '
             $1 ~ /^A/ {print $2}
             $1 ~ /^M/ {print $2}
             $1 ~ /^R/ {print $3}
-          ')
+          ' | awk -F/ '{print $1"/"$2}' | sort -u)
 
-          if [ -z "$CHANGED_FILES" ]; then
+          if [ -z "$CHANGED_FOLDERS" ]; then
             exit 0
           fi
 
           echo "Validating:"
-          echo "$CHANGED_FILES"
+          echo "$CHANGED_FOLDERS"
 
           INVALID_COUNT=0
-          while IFS= read -r f; do
-            [ -z "$f" ] && continue
-            if [ ! -f "$f" ]; then
-              echo "[SKIP] missing file: $f"
+          while IFS= read -r d; do
+            [ -z "$d" ] && continue
+            if [ ! -d "$d" ]; then
+              echo "[SKIP] missing folder: $d"
               continue
             fi
-            if ! python scripts/check_skill_md.py "$f"; then
+            if ! python scripts/validate_skill.py "$d"; then
+              echo "[ERROR] Validation failed for $d"
               INVALID_COUNT=$((INVALID_COUNT + 1))
             fi
-          done <<< "$CHANGED_FILES"
+          done <<< "$CHANGED_FOLDERS"
 
           echo ""
-          echo "$INVALID_COUNT skills failed validation."
-
           if [ "$INVALID_COUNT" -ne 0 ]; then
+            echo "[ERROR] $INVALID_COUNT skills failed validation."
             exit 1
+          else
+            echo "All skills passed validation."
           fi
 
           exit 0
\ No newline at end of file
diff --git a/scripts/validate_skill.py b/scripts/validate_skill.py
index 94617a0b..b3cc0997 100644
--- a/scripts/validate_skill.py
+++ b/scripts/validate_skill.py
@@ -4,9 +4,10 @@
 """
 
 import re
-import yaml
 from pathlib import Path
 
+import yaml
+
 def validate_skill(skill_path):
     """Basic validation of a skill"""
     skill_path = Path(skill_path)
@@ -17,7 +18,7 @@ def validate_skill(skill_path):
         return False, "SKILL.md not found"
 
     # Read and validate frontmatter
-    content = skill_md.read_text()
+    content = skill_md.read_text(encoding='utf-8', errors='replace')
     # Allow frontmatter block to appear anywhere in the file
     match = re.search(r'(?m)^---\n(.*?)\n---', content, re.DOTALL)
     if not match:
@@ -67,4 +68,19 @@ def validate_skill(skill_path):
     #     if len(description) > 1024:
     #         return False, f"Description is too long ({len(description)} characters). Maximum is 1024 characters."
 
-    return True, "Skill is valid!"
\ No newline at end of file
+    return True, "Skill is valid!"
+
+if __name__ == "__main__":
+    import sys
+
+    if len(sys.argv) != 2:
+        print("Usage: validate_skill.py path/to/SKILL.md", file=sys.stderr)
+        raise SystemExit(2)
+
+    ok, msg = validate_skill(sys.argv[1])
+    if ok:
+        print(msg)
+        raise SystemExit(0)
+    else:
+        print(msg, file=sys.stderr)
+        raise SystemExit(1)
\ No newline at end of file