mcp-libsql

## Relevant Files - `.gitignore` - Git ignore file for Node.js projects - `package.json` - Project configuration and dependencies - `tsconfig.json` - TypeScript configuration with strict mode and ES2022 target - `eslint.config.js` - ESLint configuration with TypeScript support - `.prettierrc` - Prettier configuration for code formatting - `.prettierignore` - Prettier ignore file - `vitest.config.ts` - Vitest configuration with coverage settings - `plans/mcp-libsql-server/implementation-notes.md` - Key learnings, technical details, and architecture decisions - `src/index.ts` - Main entry point for MCP server (placeholder) - `src/types/index.ts` - TypeScript type definitions for database, logging, and metrics - `src/lib/constants.ts` - Configuration constants, restricted operations, and query types - `src/lib/database.ts` - Database connection manager and connection pool implementation - `src/lib/logger.ts` - Structured logging utility with console and file output - `src/utils/performance.ts` - Performance monitoring utilities for query metrics - `src/utils/error-handler.ts` - Error handling utilities and MCP-compliant error responses - `src/__tests__/unit/database.test.ts` - Unit tests for database connection and pool - `src/__tests__/unit/logger.test.ts` - Unit tests for logging functionality - `src/lib/base-tool.ts` - Abstract base class for MCP tools with Zod validation and registry - `src/lib/server-manager.ts` - ServerManager class for lifecycle management and development mode - `src/tools/read-query.ts` - Read-only SELECT query tool implementation - `src/tools/write-query.ts` - Write operations (INSERT/UPDATE/DELETE) tool implementation - `src/tools/create-table.ts` - CREATE TABLE DDL tool implementation - `src/tools/alter-table.ts` - ALTER TABLE DDL tool implementation - `src/tools/list-tables.ts` - List all tables metadata tool implementation - `src/tools/describe-table.ts` - Table schema description tool implementation - `nodemon.json` - Nodemon configuration for development hot reloading - `src/schemas/` - Zod schemas for validation directory - `src/schemas/read-query.ts` - Enhanced Zod schema for read-query tool validation - `src/schemas/write-query.ts` - Comprehensive Zod schema for write-query tool validation with security measures - `src/schemas/create-table.ts` - Comprehensive Zod schema for create-table tool validation with DDL security measures - `src/schemas/alter-table.ts` - Comprehensive Zod schema for alter-table tool validation with security measures - `src/schemas/describe-table.ts` - Zod schema for describe-table tool with table name validation and output options - `src/schemas/list-tables.ts` - Zod schema for list-tables tool with filtering and output format options - `src/__tests__/integration/` - Integration tests directory - `src/__tests__/unit/read-query.test.ts` - Comprehensive unit tests for read-query tool - `src/__tests__/unit/write-query.test.ts` - Comprehensive unit tests for write-query tool with transaction testing - `src/__tests__/unit/create-table.test.ts` - Comprehensive unit tests for create-table tool with DDL validation testing - `src/__tests__/unit/alter-table.test.ts` - Comprehensive unit tests for alter-table tool with DDL operation testing - `src/__tests__/unit/describe-table.test.ts` - Comprehensive unit tests for describe-table tool with schema inspection testing - `src/__tests__/unit/list-tables.test.ts` - Comprehensive unit tests for list-tables tool with metadata querying testing - `src/__tests__/integration/end-to-end.test.ts` - Comprehensive integration tests for end-to-end scenarios with real database operations - `src/__tests__/unit/audit-trail.test.ts` - Audit trail logging tests to verify database operations are properly logged for security compliance - `src/__tests__/unit/connection-retry.test.ts` - Connection failure and retry scenario tests for connection pool resilience and recovery - `src/__tests__/unit/error-handler.test.ts` - Comprehensive tests for error handling utilities covering all error types and MCP error conversion - `src/__tests__/unit/performance.test.ts` - Complete tests for performance monitoring utilities with metrics creation and formatting - `src/__tests__/unit/base-tool.test.ts` - Comprehensive tests for BaseTool abstract class and ToolRegistry covering validation, execution, and schema conversion - `src/__tests__/unit/server-manager.test.ts` - Tests for ServerManager lifecycle management, status reporting, and development features - `README.md` - Setup and usage documentation ### Notes - Unit tests are saved in `src/__tests__/unit` - Integration tests are saved in `src/__tests__/integration` - All tools follow MCP protocol specifications with full input validation - Connection pooling uses libSQL client library features with health monitoring - Server lifecycle management includes graceful shutdown and development mode features - Tool system uses abstract base class pattern with centralized registry for consistency - CLI supports comprehensive configuration options with help and version commands - Development mode includes enhanced logging, status monitoring, and hot reloading - **Implementation Details**: See `implementation-notes.md` for technical learnings, architecture decisions, and development insights from Tasks 1.0-4.6 and 5.1 - **Production Status**: Tasks 4.1-4.6 successfully implemented with full DDL support, database inspection, and management capabilities - ready for production deployment - **Integration Testing**: Task 5.1 completed with comprehensive end-to-end testing covering real database workflows and tool interactions ## Tasks - [x] 1.0 Project Setup and Configuration - [x] 1.1 Initialize git repository with .gitignore for Node.js projects - [x] 1.2 Initialize pnpm and create package.json with Node.js 20+ requirement - [x] 1.3 Install core dependencies (@modelcontextprotocol/sdk, @libsql/client, zod) - [x] 1.4 Install dev dependencies (typescript, vitest, eslint, prettier, @types/node, tsx, nodemon) - [x] 1.5 Create tsconfig.json with strict mode and ES2022 target - [x] 1.6 Configure ESLint with TypeScript support and recommended rules - [x] 1.7 Configure Prettier for consistent code formatting - [x] 1.8 Set up npm scripts (build, dev, lint, format, test) - [x] 1.9 Create initial project directory structure (src/tools, src/lib, src/types, src/schemas, src/utils) - [x] 2.0 Core Database Connection and Pooling Implementation - [x] 2.1 Create database connection manager with libSQL client - [x] 2.2 Implement connection pooling with configurable min/max connections - [x] 2.3 Add automatic retry logic for failed connections (5 second intervals) - [x] 2.4 Implement connection health checks and graceful shutdown - [x] 2.5 Create logging utility with console and file output - [x] 2.6 Add performance monitoring utilities for tracking query metrics - [x] 2.7 Define constants for timeouts, limits, and restricted operations - [x] 2.8 Create error handling utilities for consistent error responses - [x] 3.0 MCP Server Setup and Tool Registration - [x] 3.1 Create main server entry point with CLI argument parsing - [x] 3.2 Implement MCP server initialization with proper metadata - [x] 3.3 Create base tool class/interface for consistent tool structure - [x] 3.4 Set up tool registration system for all 6 tools - [x] 3.5 Implement request/response handling with error boundaries - [x] 3.6 Add server lifecycle management (start, stop, reload) - [x] 3.7 Create development mode with hot reloading using nodemon - [x] 4.0 Implement Database Tools - [x] 4.1 Implement read-query tool - [x] 4.1.1 Create Zod schema for input validation - [x] 4.1.2 Implement SELECT query detection and validation - [x] 4.1.3 Add query execution with timeout handling - [x] 4.1.4 Format results with performance metrics - [x] 4.1.5 Write comprehensive unit tests - [x] 4.2 Implement write-query tool - [x] 4.2.1 Create Zod schema for input validation - [x] 4.2.2 Implement INSERT/UPDATE/DELETE detection and validation - [x] 4.2.3 Add transaction support with rollback on errors - [x] 4.2.4 Return affected rows with performance metrics - [x] 4.2.5 Write comprehensive unit tests - [x] 4.3 Implement create-table tool - [x] 4.3.1 Create Zod schema for input validation - [x] 4.3.2 Implement CREATE TABLE statement validation - [x] 4.3.3 Execute DDL with error handling - [x] 4.3.4 Return success confirmation with metrics - [x] 4.3.5 Write comprehensive unit tests - [x] 4.4 Implement alter-table tool - [x] 4.4.1 Create Zod schema for input validation - [x] 4.4.2 Implement ALTER TABLE statement validation - [x] 4.4.3 Support ADD/DROP/RENAME COLUMN operations - [x] 4.4.4 Return success confirmation with metrics - [x] 4.4.5 Write comprehensive unit tests - [x] 4.5 Implement list-tables tool - [x] 4.5.1 Query database metadata for table names - [x] 4.5.2 Filter out system tables if applicable - [x] 4.5.3 Handle empty database case - [x] 4.5.4 Return formatted table list with metrics - [x] 4.5.5 Write comprehensive unit tests - [x] 4.6 Implement describe-table tool - [x] 4.6.1 Create Zod schema for table name validation - [x] 4.6.2 Query column information and constraints - [x] 4.6.3 Format schema information clearly - [x] 4.6.4 Handle non-existent tables gracefully - [x] 4.6.5 Write comprehensive unit tests - [x] 5.0 Testing, Documentation and Final Validation - [x] 5.1 Create integration tests for end-to-end scenarios - [x] 5.2 Add logging tests to verify audit trail - [x] 5.3 Test connection failure and retry scenarios - [x] 5.4 Verify security measures (SQL injection prevention) - [x] 5.5 Write comprehensive README with setup instructions - [x] 5.6 Document all tools with examples and expected outputs - [x] 5.7 Add troubleshooting guide for common issues - [x] 5.8 Perform final validation against all acceptance criteria - [x] 5.8.1 Validate read-query tool acceptance criteria (all ✓) - [x] 5.8.2 Validate write-query tool acceptance criteria (all ✓) - [x] 5.8.3 Validate create-table tool acceptance criteria (all ✓) - [x] 5.8.4 Validate list-tables tool acceptance criteria (all ✓) - [x] 5.8.5 Validate describe-table tool acceptance criteria (all ✓) - [x] 5.8.6 Validate alter-table tool acceptance criteria (all ✓) - [x] 5.8.7 Validate general requirements (all ✓) - [x] 5.8.8 Verify CLI functionality (help, version, argument parsing) - [x] 5.8.9 Confirm 403 tests passing with comprehensive coverage - [x] 5.9 Ensure 80% test coverage target is met - [x] 5.9.1 Create comprehensive tests for error-handler.ts (100% coverage) - [x] 5.9.2 Improve tests for performance.ts (100% coverage) - [x] 5.9.3 Create comprehensive tests for base-tool.ts (100% coverage) - [x] 5.9.4 Add tests for server-manager.ts (64.09% coverage) - [x] 5.9.5 Achieve 82.64% overall coverage (exceeds 80% target) ## Future Enhancement Tasks (Post-MVP) ### 6.0 libSQL Advanced Features - [x] 6.1 ~~Implement transaction support in write-query tool~~ - **COMPLETED IN TASK 4.2** - [x] 6.1.1 ~~Add transaction mode parameter to write-query schema~~ - **DONE** - [x] 6.1.2 ~~Implement client.transaction() usage with commit/rollback~~ - **DONE** - [x] 6.1.3 ~~Add transaction error handling and recovery~~ - **DONE** - [x] 6.1.4 ~~Write comprehensive transaction tests~~ - **DONE** - [x] 6.1.5 ~~Document transaction usage patterns~~ - **DONE** - [ ] 6.2 Add batch operations support - [ ] 6.2.1 Create batch-query tool for multiple statement execution - [ ] 6.2.2 Implement client.batch() API usage - [ ] 6.2.3 Add batch validation and error handling - [ ] 6.2.4 Optimize performance for bulk operations - [ ] 6.2.5 Write batch operation tests - [x] 6.3 Add authentication support for Turso databases - [x] 6.3.1 Add --auth-token CLI parameter - [x] 6.3.2 Implement secure token handling and validation - [x] 6.3.3 Add environment variable support for tokens - [x] 6.3.4 Update connection configuration for auth - [x] 6.3.5 Document Turso authentication setup ### 7.0 MCP Advanced Features - [ ] 7.1 Implement MCP resources for database metadata - [ ] 7.1.1 Create schema resource for database structure exposure - [ ] 7.1.2 Add table metadata resources - [ ] 7.1.3 Implement query result caching as resources - [ ] 7.1.4 Add resource discovery and listing - [ ] 7.1.5 Write resource integration tests - [ ] 7.2 Enhanced error classification and reporting - [ ] 7.2.1 Implement granular MCP error codes - [ ] 7.2.2 Add context-aware error messages - [ ] 7.2.3 Improve error recovery suggestions - [ ] 7.2.4 Add error analytics and monitoring - [ ] 7.2.5 Document error handling patterns - [ ] 7.3 Consider McpServer migration for utility tools - [ ] 7.3.1 Evaluate benefits of high-level McpServer API - [ ] 7.3.2 Create proof-of-concept simple tools with McpServer - [ ] 7.3.3 Compare performance and maintainability - [ ] 7.3.4 Plan migration strategy if beneficial - [ ] 7.3.5 Update documentation for dual approaches - [ ] 7.4 Add support for multiple databases - [ ] 7.4.1 Implement database selection mechanism - [ ] 7.4.2 Add database configuration options - [ ] 7.4.3 Implement database switching logic - [ ] 7.4.4 Add database connection pooling - [ ] 7.4.5 Write database switching tests ## Enhancement Priority Matrix ### High Priority (Next Release) 1. **Batch Operations** (6.2) - Significant performance improvement 2. **Enhanced Error Classification** (7.2) - Better user experience ### Medium Priority (Future Versions) 1. **MCP Resources** (7.1) - Enhanced protocol utilization 2. **McpServer Evaluation** (7.3) - Architecture optimization 3. **Multi-database Support** (7.4) - Support multiple databases