--- name: plugin-settings description: This skill should be used when the user asks about "plugin settings", "store plugin configuration", "user-configurable plugin", ".local.md files", "plugin state files", "read YAML frontmatter", "per-project plugin settings", or wants to make plugin behavior configurable. Documents the .claude/plugin-name.local.md pattern for storing plugin-specific configuration with YAML frontmatter and markdown content. --- # Plugin Settings Pattern for Claude Code Plugins ## Overview Plugins can store user-configurable settings and state in `.claude/plugin-name.local.md` files within the project directory. This pattern uses YAML frontmatter for structured configuration and markdown content for prompts or additional context. **Key characteristics:** - File location: `.claude/plugin-name.local.md` in project root - Structure: YAML frontmatter + markdown body - Purpose: Per-project plugin configuration and state - Usage: Read from hooks, commands, and agents - Lifecycle: User-managed (not in git, should be in `.gitignore`) ## File Structure ### Basic Template ```markdown --- enabled: true setting1: value1 setting2: value2 numeric_setting: 42 list_setting: ["item1", "item2"] --- # Additional Context This markdown body can contain: - Task descriptions - Additional instructions - Prompts to feed back to Claude - Documentation or notes ``` ### Example: Plugin State File **.claude/my-plugin.local.md:** ```markdown --- enabled: true strict_mode: false max_retries: 3 notification_level: info coordinator_session: team-leader --- # Plugin Configuration This plugin is configured for standard validation mode. Contact @team-lead with questions. ``` ## Reading Settings Files ### From Hooks (Bash Scripts) **Pattern: Check existence and parse frontmatter** ```bash #!/bin/bash set -euo pipefail # Define state file path STATE_FILE=".claude/my-plugin.local.md" # Quick exit if file doesn't exist if [[ ! -f "$STATE_FILE" ]]; then exit 0 # Plugin not configured, skip fi # Parse YAML frontmatter (between --- markers) FRONTMATTER=$(sed -n '/^---$/,/^---$/{ /^---$/d; p; }' "$STATE_FILE") # Extract individual fields ENABLED=$(echo "$FRONTMATTER" | grep '^enabled:' | sed 's/enabled: *//' | sed 's/^"\(.*\)"$/\1/') STRICT_MODE=$(echo "$FRONTMATTER" | grep '^strict_mode:' | sed 's/strict_mode: *//' | sed 's/^"\(.*\)"$/\1/') # Check if enabled if [[ "$ENABLED" != "true" ]]; then exit 0 # Disabled fi # Use configuration in hook logic if [[ "$STRICT_MODE" == "true" ]]; then # Apply strict validation # ... fi ``` See `examples/read-settings-hook.sh` for complete working example. ### From Commands Commands can read settings files to customize behavior: ```markdown --- description: Process data with plugin allowed-tools: ["Read", "Bash"] --- # Process Command Steps: 1. Check if settings exist at `.claude/my-plugin.local.md` 2. Read configuration using Read tool 3. Parse YAML frontmatter to extract settings 4. Apply settings to processing logic 5. Execute with configured behavior ``` ### From Agents Agents can reference settings in their instructions: ```markdown --- name: configured-agent description: Agent that adapts to project settings --- Check for plugin settings at `.claude/my-plugin.local.md`. If present, parse YAML frontmatter and adapt behavior according to: - enabled: Whether plugin is active - mode: Processing mode (strict, standard, lenient) - Additional configuration fields ``` ## Parsing Techniques ### Extract Frontmatter ```bash # Extract everything between --- markers FRONTMATTER=$(sed -n '/^---$/,/^---$/{ /^---$/d; p; }' "$FILE") ``` ### Read Individual Fields **String fields:** ```bash VALUE=$(echo "$FRONTMATTER" | grep '^field_name:' | sed 's/field_name: *//' | sed 's/^"\(.*\)"$/\1/') ``` **Boolean fields:** ```bash ENABLED=$(echo "$FRONTMATTER" | grep '^enabled:' | sed 's/enabled: *//') # Compare: if [[ "$ENABLED" == "true" ]]; then ``` **Numeric fields:** ```bash MAX=$(echo "$FRONTMATTER" | grep '^max_value:' | sed 's/max_value: *//') # Use: if [[ $MAX -gt 100 ]]; then ``` ### Read Markdown Body Extract content after second `---`: ```bash # Get everything after closing --- BODY=$(awk '/^---$/{i++; next} i>=2' "$FILE") ``` ## Common Patterns ### Pattern 1: Temporarily Active Hooks Use settings file to control hook activation: ```bash #!/bin/bash STATE_FILE=".claude/security-scan.local.md" # Quick exit if not configured if [[ ! -f "$STATE_FILE" ]]; then exit 0 fi # Read enabled flag FRONTMATTER=$(sed -n '/^---$/,/^---$/{ /^---$/d; p; }' "$STATE_FILE") ENABLED=$(echo "$FRONTMATTER" | grep '^enabled:' | sed 's/enabled: *//') if [[ "$ENABLED" != "true" ]]; then exit 0 # Disabled fi # Run hook logic # ... ``` **Use case:** Enable/disable hooks without editing hooks.json (requires restart). ### Pattern 2: Agent State Management Store agent-specific state and configuration: **.claude/multi-agent-swarm.local.md:** ```markdown --- agent_name: auth-agent task_number: 3.5 pr_number: 1234 coordinator_session: team-leader enabled: true dependencies: ["Task 3.4"] --- # Task Assignment Implement JWT authentication for the API. **Success Criteria:** - Authentication endpoints created - Tests passing - PR created and CI green ``` Read from hooks to coordinate agents: ```bash AGENT_NAME=$(echo "$FRONTMATTER" | grep '^agent_name:' | sed 's/agent_name: *//') COORDINATOR=$(echo "$FRONTMATTER" | grep '^coordinator_session:' | sed 's/coordinator_session: *//') # Send notification to coordinator tmux send-keys -t "$COORDINATOR" "Agent $AGENT_NAME completed task" Enter ``` ### Pattern 3: Configuration-Driven Behavior **.claude/my-plugin.local.md:** ```markdown --- validation_level: strict max_file_size: 1000000 allowed_extensions: [".js", ".ts", ".tsx"] enable_logging: true --- # Validation Configuration Strict mode enabled for this project. All writes validated against security policies. ``` Use in hooks or commands: ```bash LEVEL=$(echo "$FRONTMATTER" | grep '^validation_level:' | sed 's/validation_level: *//') case "$LEVEL" in strict) # Apply strict validation ;; standard) # Apply standard validation ;; lenient) # Apply lenient validation ;; esac ``` ## Creating Settings Files ### From Commands Commands can create settings files: ```markdown # Setup Command Steps: 1. Ask user for configuration preferences 2. Create `.claude/my-plugin.local.md` with YAML frontmatter 3. Set appropriate values based on user input 4. Inform user that settings are saved 5. Remind user to restart Claude Code for hooks to recognize changes ``` ### Template Generation Provide template in plugin README: ```markdown ## Configuration Create `.claude/my-plugin.local.md` in your project: \`\`\`markdown --- enabled: true mode: standard max_retries: 3 --- # Plugin Configuration Your settings are active. \`\`\` After creating or editing, restart Claude Code for changes to take effect. ``` ## Best Practices ### File Naming ✅ **DO:** - Use `.claude/plugin-name.local.md` format - Match plugin name exactly - Use `.local.md` suffix for user-local files ❌ **DON'T:** - Use different directory (not `.claude/`) - Use inconsistent naming - Use `.md` without `.local` (might be committed) ### Gitignore Always add to `.gitignore`: ```gitignore .claude/*.local.md .claude/*.local.json ``` Document this in plugin README. ### Defaults Provide sensible defaults when settings file doesn't exist: ```bash if [[ ! -f "$STATE_FILE" ]]; then # Use defaults ENABLED=true MODE=standard else # Read from file # ... fi ``` ### Validation Validate settings values: ```bash MAX=$(echo "$FRONTMATTER" | grep '^max_value:' | sed 's/max_value: *//') # Validate numeric range if ! [[ "$MAX" =~ ^[0-9]+$ ]] || [[ $MAX -lt 1 ]] || [[ $MAX -gt 100 ]]; then echo "⚠️ Invalid max_value in settings (must be 1-100)" >&2 MAX=10 # Use default fi ``` ### Restart Requirement **Important:** Settings changes require Claude Code restart. Document in your README: ```markdown ## Changing Settings After editing `.claude/my-plugin.local.md`: 1. Save the file 2. Exit Claude Code 3. Restart: `claude` or `cc` 4. New settings will be loaded ``` Hooks cannot be hot-swapped within a session. ## Security Considerations ### Sanitize User Input When writing settings files from user input: ```bash # Escape quotes in user input SAFE_VALUE=$(echo "$USER_INPUT" | sed 's/"/\\"/g') # Write to file cat > "$STATE_FILE" <&2 exit 2 fi ``` ### Permissions Settings files should be: - Readable by user only (`chmod 600`) - Not committed to git - Not shared between users ## Real-World Examples ### multi-agent-swarm Plugin **.claude/multi-agent-swarm.local.md:** ```markdown --- agent_name: auth-implementation task_number: 3.5 pr_number: 1234 coordinator_session: team-leader enabled: true dependencies: ["Task 3.4"] additional_instructions: Use JWT tokens, not sessions --- # Task: Implement Authentication Build JWT-based authentication for the REST API. Coordinate with auth-agent on shared types. ``` **Hook usage (agent-stop-notification.sh):** - Checks if file exists (line 15-18: quick exit if not) - Parses frontmatter to get coordinator_session, agent_name, enabled - Sends notifications to coordinator if enabled - Allows quick activation/deactivation via `enabled: true/false` ### ralph-wiggum Plugin **.claude/ralph-loop.local.md:** ```markdown --- iteration: 1 max_iterations: 10 completion_promise: "All tests passing and build successful" --- Fix all the linting errors in the project. Make sure tests pass after each fix. ``` **Hook usage (stop-hook.sh):** - Checks if file exists (line 15-18: quick exit if not active) - Reads iteration count and max_iterations - Extracts completion_promise for loop termination - Reads body as the prompt to feed back - Updates iteration count on each loop ## Quick Reference ### File Location ``` project-root/ └── .claude/ └── plugin-name.local.md ``` ### Frontmatter Parsing ```bash # Extract frontmatter FRONTMATTER=$(sed -n '/^---$/,/^---$/{ /^---$/d; p; }' "$FILE") # Read field VALUE=$(echo "$FRONTMATTER" | grep '^field:' | sed 's/field: *//' | sed 's/^"\(.*\)"$/\1/') ``` ### Body Parsing ```bash # Extract body (after second ---) BODY=$(awk '/^---$/{i++; next} i>=2' "$FILE") ``` ### Quick Exit Pattern ```bash if [[ ! -f ".claude/my-plugin.local.md" ]]; then exit 0 # Not configured fi ``` ## Additional Resources ### Reference Files For detailed implementation patterns: - **`references/parsing-techniques.md`** - Complete guide to parsing YAML frontmatter and markdown bodies - **`references/real-world-examples.md`** - Deep dive into multi-agent-swarm and ralph-wiggum implementations ### Example Files Working examples in `examples/`: - **`read-settings-hook.sh`** - Hook that reads and uses settings - **`create-settings-command.md`** - Command that creates settings file - **`example-settings.md`** - Template settings file ### Utility Scripts Development tools in `scripts/`: - **`validate-settings.sh`** - Validate settings file structure - **`parse-frontmatter.sh`** - Extract frontmatter fields ## Implementation Workflow To add settings to a plugin: 1. Design settings schema (which fields, types, defaults) 2. Create template file in plugin documentation 3. Add gitignore entry for `.claude/*.local.md` 4. Implement settings parsing in hooks/commands 5. Use quick-exit pattern (check file exists, check enabled field) 6. Document settings in plugin README with template 7. Remind users that changes require Claude Code restart Focus on keeping settings simple and providing good defaults when settings file doesn't exist.