feat(prompts): inventory skill metadata and duplicate names

scripts/lib/prompt-inventory.py

@@ -0,0 +1,47 @@
+import argparse
+from collections import Counter
+from pathlib import Path
+import re
+
+
+def inventory(roots):
+    names = Counter()
+    count = metadata_bytes = body_bytes = 0
+    for root in roots:
+        for path in sorted(root.rglob('SKILL.md')):
+            content = path.read_text(encoding='utf-8-sig')
+            count += 1
+            body_bytes += len(content.encode('utf-8'))
+            header = re.match(r'\A---\r?\n(.*?)^---\s*$', content, re.MULTILINE | re.DOTALL)
+            if header:
+                metadata_bytes += len(header.group(1).encode('utf-8'))
+                name = re.search(r'^name:\s*(.+)$', header.group(1), re.MULTILINE)
+                if name:
+                    names[name.group(1).strip().strip('\"\'')] += 1
+    return count, metadata_bytes, body_bytes, sorted(name for name, total in names.items() if total > 1)
+
+
+def report(label, roots, warn_duplicates=True):
+    count, metadata, bodies, duplicates = inventory(roots)
+    print(f'{label}: {count} skill files, {metadata} frontmatter bytes (~{(metadata + 3) // 4} tokens), {bodies} lazy file bytes')
+    if duplicates and warn_duplicates:
+        print(f'WARN {label}: repeated skill names ({len(duplicates)}): {", ".join(duplicates)}')
+
+
+def main():
+    parser = argparse.ArgumentParser()
+    parser.add_argument('--home', type=Path, default=Path.home())
+    args = parser.parse_args()
+    root = Path(__file__).resolve().parents[2]
+    for client in ('codex', 'claude'):
+        report(f'Generated {client} catalog', [root / 'generated' / f'{client}-bash' / 'skills'])
+        directories = [args.home / f'.{client}' / 'skills']
+        if client == 'codex':
+            directories.append(args.home / '.agents' / 'skills')
+        report(f'Installed {client} user catalog', directories)
+        report(f'Cached {client} plugins (all versions)', [args.home / f'.{client}' / 'plugins' / 'cache'], warn_duplicates=False)
+    print('Coverage: baseline covers generated instructions only. Inventory is not measured session context; plugin caches include inactive versions. Client prompts, tool schemas and dynamic hook output are excluded. Token counts use bytes/4 estimates.')
+
+
+if __name__ == '__main__':
+    main()