mcp-memory-libsql

# System Patterns ## Architecture The system follows a modular architecture with clear separation of concerns: ### Core Components 1. **Scope Registry** (src/modules/tools/scope-registry.ts) - Simple scope collection system - Gathers required scopes at startup - Used only for initial auth setup 2. **MCP Server** (src/index.ts) - Registers and manages available tools - Handles request routing and validation - Provides consistent error handling 3. **Account Module** (src/modules/accounts/*) - OAuth Client: Implements Google OAuth 2.0 flow - Token Manager: Handles token lifecycle - Account Manager: Manages account configurations 4. **Service Modules** - Gmail Module: Implements email operations - Calendar Module: Handles calendar operations ## Key Technical Decisions 1. **Simplest Viable Design** - Minimize complexity in permission structures - Handle auth through HTTP response codes (401/403) - Move OAuth mechanics into platform infrastructure - Present simple verb-noun interfaces 2. **Tool Registration Pattern** - Tools must be registered in both ListToolsRequestSchema and CallToolRequestSchema - Follows verb-noun naming convention (e.g., list_workspace_accounts) 3. **Error Handling** - Simplified auth error handling through 401/403 responses - Automatic token refresh on auth failures - Service-specific error types - Clear authentication error guidance ## Project Structure ``` src/ ├── index.ts # MCP server implementation ├── modules/ │ ├── accounts/ # Account & auth handling │ │ ├── index.ts # Module entry point │ │ ├── manager.ts # Account management │ │ ├── oauth.ts # OAuth implementation │ │ └── token.ts # Token handling │ └── gmail/ # Gmail implementation │ ├── index.ts # Module entry point │ ├── service.ts # Gmail operations │ └── types.ts # Gmail types └── scripts/ └── setup-google-env.ts # Setup utilities ``` ## Configuration Patterns - Environment-based file paths - Separate credential storage - Account configuration management - Token persistence handling - Security through proper credential and token management