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+# CLAUDE.md
+
+This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
+
+## Overview
+
+This is the OpenHarmony Security Component Manager Service - a system ability (SA ID: 3506) that allows applications to access temporary permissions through UI components without permanent authorization. When a user clicks a security component (e.g., PasteButton, SaveButton), the app receives temporary permission to access sensitive data.
+
+## Build System
+
+This project uses OpenHarmony's GN (Generate Ninja) build system.
+
+**Main build files:**
+- `BUILD.gn` - Main build configuration
+- `security_component.gni` - Feature flags for enhancement capabilities
+- `bundle.json` - Component metadata and dependencies
+
+**Build targets:**
+- `security_component_build_module` - Main service module
+- `security_component_build_module_test` - Unit tests
+- `security_component_build_fuzz_test` - Fuzz tests
+
+**Build commands:**
+```bash
+# Build main service
+./build.sh --product-name <product> --build-variant root --build-target security_component_manager
+
+# Build tests
+./build.sh --product-name <product> --build-variant root --build-target security_component_build_module_test
+./build.sh --product-name <product> --build-variant root --build-target security_component_build_fuzz_test
+```
+
+## Architecture
+
+The codebase follows OpenHarmony's System Ability pattern with three main layers:
+
+### 1. Service Layer (`services/security_component_service/sa/`)
+- `SecCompService` - Main SystemAbility class, inherits from `SystemAbility`
+- `SecCompManager` - Core business logic manager (singleton pattern)
+- `SecCompEntity` - Represents individual security components
+- `AppStateObserver` - Monitors app lifecycle (foreground/background transitions)
+
+### 2. Framework Layer (`frameworks/`)
+- `security_component/` - Core framework implementation
+- `enhance_adapter/` - Adaptation layer for vendor enhancements
+- `common/` - Shared utilities and base classes
+
+### 3. Interface Layer (`interfaces/inner_api/`)
+- `security_component/` - Main service APIs (register, update, unregister, report click)
+- `enhance_kits/` - Enhancement configuration APIs
+- `security_component_common/` - Common utilities and definitions
+
+## Component Types
+
+- `PasteButton` - Clipboard access
+- `SaveButton` - Save operations
+
+## Testing
+
+**Unit tests:** `frameworks/*/test/` and `services/*/test/unittest/`
+**Fuzz tests:** `test/fuzztest/security_component/` - Tests all major APIs
+**Test mocks:** `test/fuzztest/security_component/mock/`
+
+## Important Design Patterns
+
+- **Singleton**: `SecCompManager` manages global state
+- **Observer**: `AppStateObserver` for app lifecycle events
+- **Factory**: Component creation and type handling
+- **Delayed tasks**: `DelayExitTask` for cleanup operations
+
+## Dependencies
+
+Key OpenHarmony components:
+- `samgr` - System Ability Manager
+- `ipc_core` - IPC communication
+- `access_token` - Permission tokens
+- `ability_runtime` - Application lifecycle
+- `window_manager` - Window management
+- `hilog` - Logging
+- `hisysevent` - System events