Access-DevTool-MCP

# Access-DevTool-MCP [](https://opensource.org/licenses/MIT) [](https://dotnet.microsoft.com/) [](https://www.microsoft.com/) **Access-DevTool-MCP** is a Model Context Protocol (MCP) server that enables Claude AI to interact with Microsoft Access databases through COM Interop automation. Modify forms and reports, modify and execute VBA code, and manage database objects programmatically. ## Features - 🗄️ **Database Connection** - Connect to and manage .accdb and .mdb files - 📋 **Object Management** - Create, read, update, and delete forms, reports, modules, queries, and macros - 💾 **VBA Automation** - Execute VBA procedures, read/modify VBA source code, compile modules - 🎨 **Form Design** - Inspect and modify form controls, properties, and layouts - 📊 **Report Management** - Export, import, and delete reports - ⚙️ **Application Control** - Execute Access commands, invoke COM Interop methods, evaluate expressions - 🔍 **Database Inspection** - List and explore all database objects with metadata - 📤 **Export/Import** - Round-trip export/import of database objects as text (SaveAsText/LoadFromText) ## Quick Links - 📖 **[Setup Guide](MCP_SETUP_GUIDE.md)** - Complete installation and usage guide - ⚡ **[Quick Start](QUICK_START.md)** - Get running in 30 seconds - 🏗️ **[Architecture](ARCHITECTURE.md)** - Technical deep dive and design documentation - 🤖 **[Claude Code Skill](.claude/skills/Access-DevTool-helper.md)** - Expert guidance for using Access-DevTool-MCP ## Requirements ### System - **Windows Operating System** (Windows 10 or later recommended) - **32-bit Microsoft Access** (Office 2016 SP1+, 2019, 2021, or Microsoft 365) - ⚠️ **64-bit Access is NOT supported** - **.NET Runtime** (included with published builds) ### Software - **Microsoft Visual Studio 2022** or later (for building from source) - **Git** (optional, for cloning the repository) ## Installation ### Option 1: Use Published Build (Recommended) 1. **Download** the latest release from the [Releases](../../releases) page 2. **Extract** to a location like `C:\Tools\Access-DevTool-MCP\` 3. **Verify** both executables are present: - `Access-DevTool-MCP.exe` - `Access-DevTool-Agent.exe` 4. Skip to [Configuration](#configuration) ### Option 2: Build from Source ```bash # Clone the repository git clone https://github.com/YOUR_ORG/Access-DevTool-MCP.git cd Access-DevTool-MCP # Open in Visual Studio # Build > Build Solution (Ctrl+Shift+B) # Publish the main project (required before using with Claude) # Right-click Access-DevTool-MCP > Publish ``` Published files will be in the `Published` folder. This includes both `Access-DevTool-MCP.exe` and `Access-DevTool-Agent.exe`, which are required for Claude to use the MCP server. ## Configuration After building and publishing (or downloading a release), configure Claude Code to use Access-DevTool-MCP by pointing to the published executable. **Important:** Make sure you have completed the build and publish steps above. Claude needs access to both `Access-DevTool-MCP.exe` and `Access-DevTool-Agent.exe` from the `Published` folder. ### Claude Code CLI Add to `~/.claude/settings.json`: ```json { "mcpServers": { "access-devtool-mcp": { "command": "C:\\Tools\\Access-DevTool-MCP\\Access-DevTool-MCP.exe", "args": [] } } } ``` ### Claude Code Desktop 1. Open **Settings > MCP Servers** 2. Click **"Add Server"** 3. Enter: - **Name:** `access-devtool-mcp` - **Command:** `C:\\Tools\\Access-DevTool-MCP\\Access-DevTool-MCP.exe` 4. Click **"Add"** ### Optional: Auto-Connect to a Database (Advanced) You can optionally pass a database path as an argument to auto-connect when the server starts. However, **this is not recommended for normal usage** because: - Auto-connect only happens once when the MCP server first starts - It doesn't persist across Claude Code restarts - It can mask connection errors if the database becomes unavailable - You lose explicit control over when the connection opens/closes **For normal workflows, explicitly call `connect_access` as part of your task.** This gives you: - Clear visibility into when connections open and close - Better error handling and recovery - Ability to work with multiple databases across sessions If you want to auto-connect for testing/development purposes: ```json { "mcpServers": { "Access-DevTool": { "command": "C:\\Tools\\Access-DevTool-MCP\\Access-DevTool-MCP.exe", "args": ["C:\\Users\\YourName\\MyDatabase.accdb"] } } } ``` **When using auto-connect:** Still include an explicit `disconnect_access` call when you're done, as the connection persists for the entire Claude Code session. ## Usage ### ⚠️ Before You Start: Backup Your Database **Always create a backup of your Access database before using this tool.** This MCP server provides full programmatic access to your database, including the ability to modify code, forms, and data. ```bash # Simple backup example copy "C:\Users\YourName\MyDatabase.accdb" "C:\Users\YourName\MyDatabase_backup_2026-05-09.accdb" ``` ### 🤖 Using the Claude Code Skill for Guidance **Access-DevTool-MCP includes a built-in Claude Code skill** that provides expert guidance on using all 40+ tools safely and effectively. When working with this project in Claude Code, the skill is automatically available. **The skill helps you with:** - **Safe operation patterns** - Recommended workflows for connecting, modifying objects, and disconnecting - **All 40+ tools** - Detailed reference for each tool, object type codes, and common operations - **Best practices** - Backup strategies, code review, version control, and gradual testing - **Troubleshooting** - Solutions for common connection issues, dialog handling, and lockfile behavior - **Code examples** - Ready-to-use patterns for forms, reports, VBA, and database inspection Simply ask Claude for help with any task, and the skill will provide context-aware guidance tailored to Access-DevTool-MCP. For example: - "How do I safely modify a form control?" - "What's the pattern for exporting forms?" - "Help me understand the lockfile behavior" ### Important Usage Notes #### Who Should Use This Tool **Access-DevTool-MCP is intended for developers and power users who need to modify Access applications**, not for end users. This tool provides full programmatic access to database structure, code, and design. Use it only if you understand database design and are comfortable modifying VBA code and database objects. #### Getting Started Checklist 1. **Close Access before connecting** - Make sure Microsoft Access is completely closed before you ask Claude to connect to your database 2. **Ask Claude to disconnect when finished** - Always request Claude to disconnect from the database when your work is complete 3. **Keep Access visible** - Once connected, Access may display dialog boxes during automation. Keep the Access window visible and be ready to click appropriate buttons if needed 4. **Understand the lockfile** - While connected, Access creates a lockfile (`.ldb` or `.laccdb`) that prevents other connections from saving changes. Disconnecting removes this lockfile and allows normal Access usage #### Connection Behavior - **One connection at a time** - The MCP server maintains one connection per database - **Lockfile prevents concurrent saves** - While connected via the MCP server, other Access instances cannot save changes to the same database - **Dialog boxes require interaction** - Some Access operations may display dialog boxes. You need to interact with these dialogs by clicking buttons in the Access window #### Disconnection Important Always disconnect when finished: ``` User: "Please disconnect from the database" ``` Disconnecting: - Closes the Access connection - Removes the lockfile - Allows other Access instances to save changes normally - Prevents accidental modifications ### Basic Examples #### 1. List All Forms ``` User: "In my database at C:\Users\<UserName>\MyDB.accdb, list all forms" Claude will: - Connect to the database - Enumerate all forms - Return the list of form names ``` #### 2. Export a Form for Review ``` User: "Export the 'ContactForm' from my database so I can review it" Claude will: - Open the form in design view - Extract the complete form definition - Display it as text for your review ``` #### 3. Modify a Form Control ``` User: "Change the label text on 'Label1' in the 'MainForm' to 'New Label Text'" Claude will: - Open the form - Locate the control - Change the property - Save the form ``` #### 4. Execute VBA Code ``` User: "Add a procedure called 'LogEvent' to the 'Utilities' module that logs messages" Claude will: - Review the code with you first - Add the procedure to the module - Compile to verify syntax ``` #### 5. Get Database Metadata ``` User: "Show me all the queries in my database and their SQL" Claude will: - Connect to the database - Extract all query definitions with SQL text - Display them in a readable format ``` ## Available Tools Access-DevTool-MCP exposes 40+ tools for database automation: | Category | Tools | |----------|-------| | **Connection** | connect_access, disconnect_access, is_connected | | **Enumeration** | get_forms, get_reports, get_modules, get_queries, get_macros, get_vba_projects | | **Form Design** | open_form, close_form, get_form_controls, get_control_properties, set_control_property | | **VBA** | get_vba_code, set_vba_code, add_vba_procedure, compile_vba | | **Objects** | export_object_to_text, import_object_from_text, delete_object | | **Application** | get_application_info, get_option, set_option, eval_expression | | **Execution** | run_procedure, run_command, invoke_application_method, invoke_docmd_method | | **Reports** | export_report_to_text, import_report_from_text, delete_report | See [MCP_SETUP_GUIDE.md](MCP_SETUP_GUIDE.md#available-tools) for complete tool documentation. ## Troubleshooting ### "64-bit Microsoft Access is installed but is not supported" **Solution:** Install 32-bit Office/Access. ```bash # Check your Access version # File > Account > About Access button Look for "32-bit" or "64-bit" ``` ### "Access-DevTool-Agent.exe not found" **Solution:** Rebuild and republish the solution. The agent must be in the same folder as the MCP server executable. ### Connection Timeout **Solution:** Verify: - 32-bit Access is installed - Database file exists and is readable - Database file is not corrupted - You have read/write permissions on the file ### Database Becomes Corrupted **Solution:** Immediately restore from your backup. For more troubleshooting, see [MCP_SETUP_GUIDE.md#troubleshooting](MCP_SETUP_GUIDE.md#troubleshooting). ## Architecture Access-DevTool-MCP uses a two-process architecture: ``` Claude → Access-DevTool-MCP.exe (.NET 10) ↓ (Named Pipe IPC) Access-DevTool-Agent.exe (.NET 4.8 COM Interop Worker) ↓ (Access COM Interop) Microsoft Access ``` For technical details, see [ARCHITECTURE.md](ARCHITECTURE.md). ## Security & Best Practices ### Backups - ✅ Always maintain recent backups before making changes - ✅ Test backup restoration procedures - ✅ Keep multiple versions for rollback capability ### Code Review - ✅ Review all VBA code before adding it to your database - ✅ Start with read-only operations (list, export) - ✅ Test changes on a copy first ### Version Control - ✅ Use export tools to backup database objects - ✅ Store exports in Git for version tracking - ✅ Track changes over time ## Limitations - **32-bit only** - 64-bit Access not supported - **Single connection** - One database at a time per instance - **Windows only** - Requires Windows and COM Interop - **No datasheet operations** - Table data editing requires other tools - **No report preview** - Can modify reports but not preview them ## Contributing Contributions are welcome! Please: 1. Fork the repository 2. Create a feature branch (`git checkout -b feature/amazing-feature`) 3. Commit your changes (`git commit -m 'Add amazing feature'`) 4. Push to the branch (`git push origin feature/amazing-feature`) 5. Open a Pull Request ## Building from Source ### Prerequisites - Visual Studio 2022 or later - .NET 10 SDK - .NET Framework 4.8 (for the COM Interop worker) ### Build Steps ```bash # Clone and navigate git clone https://github.com/YOUR_ORG/Access-DevTool-MCP.git cd Access-DevTool-MCP # Build all projects dotnet build # Or use Visual Studio # Build > Build Solution (Ctrl+Shift+B) # Publish for distribution # Right-click Access-DevTool-MCP project > Publish # Output goes to ./Published folder ``` ## Testing ```bash # Run unit tests dotnet test Access-DevTool-MCP-Tests.csproj dotnet test Access-DevTool-MCP-Tests-Net10.csproj ``` ## License This project is licensed under the MIT License - see the [LICENSE](LICENSE) file for details. ## Support - 🤖 **Interactive assistance:** Use the [Access-DevTool-MCP Helper skill](.claude/skills/Access-DevTool-helper.md) in Claude Code for expert guidance - 📖 **Full documentation:** See [MCP_SETUP_GUIDE.md](MCP_SETUP_GUIDE.md) - ⚡ **Quick start:** See [QUICK_START.md](QUICK_START.md) - 🏗️ **Architecture details:** See [ARCHITECTURE.md](ARCHITECTURE.md) - 🐛 **Report issues:** Use the [Issues](../../issues) page - 💬 **Discussions:** Start a [Discussion](../../discussions) ## Roadmap - [ ] Multi-database session support - [ ] Transaction batching - [ ] Datasheet view operations - [ ] Report preview generation - [ ] VBA syntax validation - [ ] Database schema export (DDL scripts) ## Changelog See [CHANGELOG.md](CHANGELOG.md) for version history and updates. ## Credits - Built with [Model Context Protocol](https://modelcontextprotocol.io/) - Uses Microsoft Office Interop (strongly-typed COM Interop) for Access automation - Designed to work seamlessly with Claude AI ## Disclaimer This tool provides full programmatic access to Microsoft Access databases. Use it carefully and maintain backups of your data. The developers are not responsible for data loss or corruption resulting from incorrect usage. --- **Last Updated:** May 9, 2026 **Version:** 1.0.0 **Status:** Active Development