#!/usr/bin/env python3
"""
Parses skills/_index.json and detects relevant skills for current project.
Outputs available skills for SessionStart hook.
"""
import json
import fnmatch
import sys
from pathlib import Path
# Add hooks lib to path
sys.path.insert(0, str(Path(__file__).parent / "lib"))
from workspace import get_skills_dir
def get_skills_index_path() -> Path:
"""
Get path to skills index.
Priority:
1. MCP_WORKSPACE/skills/_index.json
2. CLAUDE_PLUGIN_ROOT/skills/_index.json
3. ~/.claude/skills/_index.json (user fallback)
"""
# Check workspace-based skills dir first
user_fallback = Path.home() / ".claude" / "skills"
skills_dir = get_skills_dir(user_fallback)
skills_index = skills_dir / "_index.json"
if skills_index.exists():
return skills_index
# Fall back to user's ~/.claude/skills
return user_fallback / "_index.json"
def load_index():
"""Load skills index from detected path."""
index_path = get_skills_index_path()
if not index_path.exists():
return {"skills": {}}
with open(index_path) as f:
return json.load(f)
def check_package_json(packages_to_match):
"""Check if any packages match in package.json dependencies."""
pkg_path = Path("package.json")
if not pkg_path.exists():
return []
try:
with open(pkg_path) as f:
pkg = json.load(f)
all_deps = set()
for key in ["dependencies", "devDependencies", "peerDependencies"]:
all_deps.update(pkg.get(key, {}).keys())
matched = []
for pattern in packages_to_match:
if "*" in pattern:
for dep in all_deps:
if fnmatch.fnmatch(dep, pattern):
matched.append(dep)
elif pattern in all_deps:
matched.append(pattern)
return matched
except (json.JSONDecodeError, IOError):
return []
def detect_skills(index):
"""Detect which skills are relevant for current project."""
cwd = Path.cwd()
cwd_name = cwd.name
detected = []
for skill_name, config in index.get("skills", {}).items():
reasons = []
# Check project markers (files that indicate project type)
for marker in config.get("projectMarkers", []):
if (cwd / marker).exists():
reasons.append(f"{marker} present")
# Check directory patterns
for pattern in config.get("directoryPatterns", []):
if fnmatch.fnmatch(cwd_name, pattern):
reasons.append(f"directory matches {pattern}")
# Check packages
matched_pkgs = check_package_json(config.get("packages", []))
if matched_pkgs:
reasons.append(f"packages: {', '.join(matched_pkgs[:3])}")
if reasons:
detected.append({
"skill": skill_name,
"reasons": reasons,
"hint": config.get("hint", f"Use /{skill_name}")
})
return detected
def main():
index = load_index()
detected = detect_skills(index)
# Output to stdout with exit 0 for transcript visibility
if detected:
skills = [d["skill"] for d in detected]
output = f"[Skills] {', '.join(skills)}"
else:
all_skills = sorted(index.get("skills", {}).keys())
output = f"[Skills] {', '.join(all_skills)}"
print(output) # stdout, visible in transcript
sys.exit(0)
if __name__ == "__main__":
main()
