Revert "Rework skill validator script (#11)"

.github/scripts/validate-skills.sh

@@ -0,0 +1,70 @@
+#!/bin/bash
+# Validates all skill directories changed in a pull request.
+#
+# Usage: validate-skills.sh <base-ref>
+#   base-ref  The base branch name to diff against (e.g. "main").
+#             When omitted or when the remote is unavailable, all skills are validated.
+#
+# Exit codes:
+#   0  All validated skills passed.
+#   1  One or more skills failed validation.
+
+# -e is intentionally omitted: all error paths are handled explicitly,
+# so abort-on-error would conflict with the || FAILED=1 accumulator pattern.
+set -uo pipefail
+
+BASE_REF="${1:-}"
+
+# Find unique skill directories containing files changed in this PR.
+# The three-dot diff requires fetch-depth: 0 and a properly configured remote,
+# which is always the case on GitHub Actions but may not be in local act runs.
+changed_skills=()
+if [ -n "$BASE_REF" ]; then
+  mapfile -t changed_skills < <(git diff --name-only "origin/${BASE_REF}...HEAD" -- skills/ \
+    2>/dev/null \
+    | cut -d'/' -f2 \
+    | sort -u \
+    | grep -v '^$')
+fi
+
+if [ "${#changed_skills[@]}" -eq 0 ]; then
+  # Fallback: validate all skill directories (e.g. when git remote is unavailable
+  # in local act testing, or when a PR only deletes files with no remaining dirs).
+  echo "Could not determine changed skills from git diff; validating all skills."
+  mapfile -t changed_skills < <(find skills -mindepth 1 -maxdepth 1 -type d -exec basename {} \; | sort -u)
+fi
+
+if [ "${#changed_skills[@]}" -eq 0 ]; then
+  echo "No skill directories found, skipping validation."
+  exit 0
+fi
+
+FAILED=0
+for skill in "${changed_skills[@]}"; do
+  # Skip skills whose directories were deleted in this PR.
+  if [ ! -d "skills/$skill" ]; then
+    echo "Skipping deleted skill: $skill"
+    continue
+  fi
+
+  # Run validation with markdown output so the result is written to the job
+  # summary in one pass. --emit-annotations works with any output format, so
+  # inline PR annotations are still emitted alongside the markdown report.
+  # We use process substitution to:
+  # 1. Send all output (including ::error commands) to stdout for GitHub Actions
+  # 2. Filter out ::error/::warning/::notice lines before writing to the summary
+  skill-validator check --strict --emit-annotations -o markdown "skills/$skill/" \
+    | tee >(grep -v '^::' >> "${GITHUB_STEP_SUMMARY:-/dev/null}") || FAILED=1
+done
+
+if [ $FAILED -ne 0 ]; then
+  echo ""
+  echo "❌ Skill validation failed!"
+  echo ""
+  echo "📋 See the Job Summary for detailed validation results:"
+  echo "   https://github.com/$GITHUB_REPOSITORY/actions/runs/$GITHUB_RUN_ID"
+  echo ""
+fi
+
+exit $FAILED
+

.github/workflows/validate-skills.yml

@@ -2,12 +2,17 @@ name: Validate Skills
 
 on:
   pull_request:
+    paths:
+      - "skills/**"
 
 jobs:
   validate:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v6
+        with:
+          # Full history is needed so git diff can compare against the base branch
+          fetch-depth: 0
 
       - name: Set up Go
         uses: actions/setup-go@v6
@@ -18,5 +23,5 @@ jobs:
       - name: Install skill-validator
         run: go install github.com/agent-ecosystem/skill-validator/cmd/skill-validator@latest
 
-      - name: Validate all skills
-        run: bash tools/validate-skills.sh
+      - name: Validate changed skills
+        run: bash .github/scripts/validate-skills.sh "${{ github.base_ref }}"