[Infra, PoC] Add static eval via skill-validator

.github/workflows/skill-check.yml

@@ -0,0 +1,216 @@
+name: Skill Validator — PR Gate
+
+on:
+  pull_request:
+    branches: [staged]
+    types: [opened, synchronize, reopened]
+    paths:
+      - "skills/**"
+      - "agents/**"
+      - "plugins/**/skills/**"
+      - "plugins/**/agents/**"
+
+permissions:
+  contents: read
+  pull-requests: write
+
+jobs:
+  skill-check:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5 # v4.3.1
+        with:
+          fetch-depth: 0
+
+      # ── Download & cache skill-validator ──────────────────────────
+      - name: Get cache key date
+        id: cache-date
+        run: echo "date=$(date +%Y-%m-%d)" >> "$GITHUB_OUTPUT"
+
+      - name: Restore skill-validator from cache
+        id: cache-sv
+        uses: actions/cache/restore@cdf6c1fa76f9f475f3d7449005a359c84ca0f306 # v5.0.3
+        with:
+          path: .skill-validator
+          key: skill-validator-linux-x64-${{ steps.cache-date.outputs.date }}
+          restore-keys: |
+            skill-validator-linux-x64-
+
+      - name: Download skill-validator
+        if: steps.cache-sv.outputs.cache-hit != 'true'
+        run: |
+          mkdir -p .skill-validator
+          curl -fsSL \
+            "https://github.com/dotnet/skills/releases/download/skill-validator-nightly/skill-validator-linux-x64.tar.gz" \
+            -o .skill-validator/skill-validator-linux-x64.tar.gz
+          tar -xzf .skill-validator/skill-validator-linux-x64.tar.gz -C .skill-validator
+          rm .skill-validator/skill-validator-linux-x64.tar.gz
+          chmod +x .skill-validator/skill-validator
+
+      - name: Save skill-validator to cache
+        if: steps.cache-sv.outputs.cache-hit != 'true'
+        uses: actions/cache/save@cdf6c1fa76f9f475f3d7449005a359c84ca0f306 # v5.0.3
+        with:
+          path: .skill-validator
+          key: skill-validator-linux-x64-${{ steps.cache-date.outputs.date }}
+
+      # ── Detect changed skills & agents ────────────────────────────
+      - name: Detect changed skills and agents
+        id: detect
+        run: |
+          CHANGED_FILES=$(git diff --name-only origin/${{ github.base_ref }}...HEAD)
+
+          # Extract unique skill directories that were touched
+          SKILL_DIRS=$(echo "$CHANGED_FILES" | grep -oP '^skills/[^/]+' | sort -u || true)
+
+          # Extract agent files that were touched
+          AGENT_FILES=$(echo "$CHANGED_FILES" | grep -oP '^agents/[^/]+\.agent\.md$' | sort -u || true)
+
+          # Extract plugin skill directories
+          PLUGIN_SKILL_DIRS=$(echo "$CHANGED_FILES" | grep -oP '^plugins/[^/]+/skills/[^/]+' | sort -u || true)
+
+          # Extract plugin agent files
+          PLUGIN_AGENT_FILES=$(echo "$CHANGED_FILES" | grep -oP '^plugins/[^/]+/agents/[^/]+\.agent\.md$' | sort -u || true)
+
+          # Build CLI arguments for --skills
+          SKILL_ARGS=""
+          for dir in $SKILL_DIRS $PLUGIN_SKILL_DIRS; do
+            if [ -d "$dir" ]; then
+              SKILL_ARGS="$SKILL_ARGS $dir"
+            fi
+          done
+
+          # Build CLI arguments for --agents
+          AGENT_ARGS=""
+          for f in $AGENT_FILES $PLUGIN_AGENT_FILES; do
+            if [ -f "$f" ]; then
+              AGENT_ARGS="$AGENT_ARGS $f"
+            fi
+          done
+
+          SKILL_COUNT=$(echo "$SKILL_ARGS" | xargs -n1 2>/dev/null | wc -l || echo 0)
+          AGENT_COUNT=$(echo "$AGENT_ARGS" | xargs -n1 2>/dev/null | wc -l || echo 0)
+          TOTAL=$((SKILL_COUNT + AGENT_COUNT))
+
+          echo "skill_args=$SKILL_ARGS" >> "$GITHUB_OUTPUT"
+          echo "agent_args=$AGENT_ARGS" >> "$GITHUB_OUTPUT"
+          echo "total=$TOTAL" >> "$GITHUB_OUTPUT"
+          echo "skill_count=$SKILL_COUNT" >> "$GITHUB_OUTPUT"
+          echo "agent_count=$AGENT_COUNT" >> "$GITHUB_OUTPUT"
+
+          echo "Found $SKILL_COUNT skill dir(s) and $AGENT_COUNT agent file(s) to check."
+
+      # ── Run skill-validator check ─────────────────────────────────
+      - name: Run skill-validator check
+        id: check
+        if: steps.detect.outputs.total != '0'
+        run: |
+          SKILL_ARGS="${{ steps.detect.outputs.skill_args }}"
+          AGENT_ARGS="${{ steps.detect.outputs.agent_args }}"
+
+          CMD=".skill-validator/skill-validator check --verbose"
+
+          if [ -n "$SKILL_ARGS" ]; then
+            CMD="$CMD --skills $SKILL_ARGS"
+          fi
+
+          if [ -n "$AGENT_ARGS" ]; then
+            CMD="$CMD --agents $AGENT_ARGS"
+          fi
+
+          echo "Running: $CMD"
+
+          # Capture output; don't fail the workflow (warn-only mode)
+          set +e
+          OUTPUT=$($CMD 2>&1)
+          EXIT_CODE=$?
+          set -e
+
+          echo "exit_code=$EXIT_CODE" >> "$GITHUB_OUTPUT"
+
+          # Save output to file (multi-line safe)
+          echo "$OUTPUT" > sv-output.txt
+
+          echo "$OUTPUT"
+
+      # ── Post / update PR comment ──────────────────────────────────
+      - name: Post PR comment with results
+        if: steps.detect.outputs.total != '0'
+        uses: actions/github-script@f28e40c7f34bde8b3046d885e986cb6290c5673b # v7.1.0
+        with:
+          script: |
+            const fs = require('fs');
+
+            const marker = '<!-- skill-validator-results -->';
+            const output = fs.readFileSync('sv-output.txt', 'utf8').trim();
+            const exitCode = '${{ steps.check.outputs.exit_code }}';
+            const skillCount = parseInt('${{ steps.detect.outputs.skill_count }}', 10);
+            const agentCount = parseInt('${{ steps.detect.outputs.agent_count }}', 10);
+            const totalChecked = skillCount + agentCount;
+
+            // Count errors, warnings, advisories from output
+            const errorCount = (output.match(/\bError\b/gi) || []).length;
+            const warningCount = (output.match(/\bWarning\b/gi) || []).length;
+            const advisoryCount = (output.match(/\bAdvisory\b/gi) || []).length;
+
+            let statusLine;
+            if (errorCount > 0) {
+              statusLine = `**${totalChecked} resource(s) checked** | ⛔ ${errorCount} error(s) | ⚠️ ${warningCount} warning(s) | ℹ️ ${advisoryCount} advisory(ies)`;
+            } else if (warningCount > 0) {
+              statusLine = `**${totalChecked} resource(s) checked** | ⚠️ ${warningCount} warning(s) | ℹ️ ${advisoryCount} advisory(ies)`;
+            } else {
+              statusLine = `**${totalChecked} resource(s) checked** | ✅ All checks passed`;
+            }
+
+            const body = [
+              marker,
+              '## 🔍 Skill Validator Results',
+              '',
+              statusLine,
+              '',
+              '<details>',
+              '<summary>Full output</summary>',
+              '',
+              '```',
+              output,
+              '```',
+              '',
+              '</details>',
+              '',
+              exitCode !== '0'
+                ? '> **Note:** Errors were found. These are currently reported as warnings and do not block merge. Please review and address when possible.'
+                : '',
+            ].join('\n');
+
+            // Find existing comment with our marker
+            const { data: comments } = await github.rest.issues.listComments({
+              owner: context.repo.owner,
+              repo: context.repo.repo,
+              issue_number: context.issue.number,
+              per_page: 100,
+            });
+
+            const existing = comments.find(c => c.body.includes(marker));
+
+            if (existing) {
+              await github.rest.issues.updateComment({
+                owner: context.repo.owner,
+                repo: context.repo.repo,
+                comment_id: existing.id,
+                body,
+              });
+              console.log(`Updated existing comment ${existing.id}`);
+            } else {
+              await github.rest.issues.createComment({
+                owner: context.repo.owner,
+                repo: context.repo.repo,
+                issue_number: context.issue.number,
+                body,
+              });
+              console.log('Created new PR comment');
+            }
+
+      - name: Post skip notice if no skills changed
+        if: steps.detect.outputs.total == '0'
+        run: echo "No skill or agent files changed in this PR — skipping validation."