# MSSQL LocalDB MCP [Health: Active]

**Category:** 🗄️ Databases  
**Repository:** https://github.com/hermessilva/LocalDB-MCP  
**GitHub Stars:** 1  
**Views:** 0  
**Installs:** 0  
**Upvotes:** 0  
**Directory Page:** https://allmcps.com/mcp/mssql-localdb-mcp

## Description
MCP server for SQL Server Express LocalDB on Windows: manage instances, run T-SQL, discover DBs

## Claude Desktop Quick Installation
Heuristic fallback — verify the package name and runner against the repository README before running it. Uses `npx` (confidence: low):

```json
"mcpServers": {
  "mssql-localdb-mcp": {
    "command": "npx",
    "args": ["-y","mssql-localdb-mcp"]
  }
}
```

## Documentation & README

# mssql-localdb-mcp

Rust [MCP](https://modelcontextprotocol.io) server for SQL Server Express LocalDB on Windows. Gives AI agents (Claude Desktop, Claude Code, and any MCP client) full control over LocalDB instances: create/manage instances, run any T-SQL script, find loose database files in project folders and attach them, introspect schema.

> Status: MVP (Phase 1) functional and tested against real LocalDB — see `docs/PLANNING.md` for the roadmap and current phase.

## Why

Existing MCP tools for SQL Server assume an already-configured remote server and require an external runtime (Python, .NET, Node). This project is:
- **Single Rust binary**, no external runtime, no Docker.
- **LocalDB-focused**: local dev workflow — find a loose `.mdf` in a project folder, attach it, run a script, no need to open SSMS.
- **Windows-only by design**, not a generic multi-database abstraction.

## Requirements

- Windows with SQL Server Express LocalDB installed (`SqlLocalDB.exe` on `PATH`).
- A compatible MCP client (Claude Desktop, Claude Code, etc.).

## Installation

### Via MCP Registry

Published on the [official MCP Registry](https://registry.modelcontextprotocol.io) as `io.github.hermessilva/mssql-localdb-mcp`. Install through any MCP client that supports the registry.

### Via VS Code extension

The [`vscode-extension/`](https://github.com/hermessilva/LocalDB-MCP/blob/HEAD/vscode-extension/) directory packages the server as a VS Code extension that registers it automatically through the MCP provider API (VS Code 1.101+), with the Windows binary bundled — nothing to download or configure by hand. Build the `.vsix` locally with:

```powershell
./build-vsix.ps1                 # bumps the build segment; -Version x.y.z or -NoBump to control it
code --install-extension .\mssql-localdb-mcp-1.0.1-win32-x64.vsix
```

The extension has its own version line, independent from `Cargo.toml` — the crate version is what
the `vX.Y.Z` tag and the MCP Registry publish.

### Via Claude Code plugin

The [`claude-plugin/`](https://github.com/hermessilva/LocalDB-MCP/blob/HEAD/claude-plugin/) directory in this repo is a self-contained Claude Code plugin (bundles the Windows binary directly, no separate download). Load it directly with:

```powershell
claude --plugin-dir path\to\LocalDB-MCP\claude-plugin
```

Submitted to the [`claude-community` marketplace](https://github.com/anthropics/claude-plugins-community) for review — once approved, install it with `claude plugin marketplace add anthropics/claude-plugins-community` followed by `claude plugin install mssql-localdb-mcp@claude-community`.

### From source

Requires [Rust](https://rustup.rs) and LocalDB installed.

```powershell
git clone https://github.com/hermessilva/LocalDB-MCP.git
cd LocalDB-MCP
cargo build --release
```

Binary at `target\release\mssql-localdb-mcp.exe`.

### Configure `config.toml`

`db_scan_folder` requires at least one explicitly allowed root — without it, the tool refuses to run. Create `%APPDATA%\mssql-localdb-mcp\config.toml`:

```toml
# Windows paths in TOML need single quotes (literal string) — double
# quotes interpret \U... as a unicode escape and break parsing.
scan_allowlist = ['C:\Users\YourUser\source\repos']
scan_max_depth = 6
default_query_timeout_secs = 30
default_max_rows = 1000
```

### Configure in your MCP client

**Claude Desktop / Claude Code** (`claude_desktop_config.json` or equivalent):

```json
{
  "mcpServers": {
    "mssql-localdb": {
      "command": "C:\\path\\to\\LocalDB-MCP\\target\\release\\mssql-localdb-mcp.exe"
    }
  }
}
```

**Claude Code via CLI:**

```powershell
claude mcp add mssql-localdb -- "C:\path\to\LocalDB-MCP\target\release\mssql-localdb-mcp.exe"
```

After that, the agent has access to the `localdb_*`, `sql_*`, and `db_*` tools — see [`docs/MCP_SPEC.md`](https://github.com/hermessilva/LocalDB-MCP/blob/HEAD/docs/MCP_SPEC.md) for the full list.

## Documentation

- [`docs/PLANNING.md`](https://github.com/hermessilva/LocalDB-MCP/blob/HEAD/docs/PLANNING.md) — roadmap, phases, scope of each milestone.
- [`docs/ARCHITECTURE.md`](https://github.com/hermessilva/LocalDB-MCP/blob/HEAD/docs/ARCHITECTURE.md) — modules, technical decisions, data flow.
- [`docs/MCP_SPEC.md`](https://github.com/hermessilva/LocalDB-MCP/blob/HEAD/docs/MCP_SPEC.md) — exact contract of every tool/resource/prompt exposed.
- [`docs/SECURITY.md`](https://github.com/hermessilva/LocalDB-MCP/blob/HEAD/docs/SECURITY.md) — threat model and guardrails.
- [`CLAUDE.md`](https://github.com/hermessilva/LocalDB-MCP/blob/HEAD/CLAUDE.md) — guide for AI agents working in this repository.
- [`CONTRIBUTING.md`](https://github.com/hermessilva/LocalDB-MCP/blob/HEAD/CONTRIBUTING.md) — how to contribute.
- [`CHANGELOG.md`](https://github.com/hermessilva/LocalDB-MCP/blob/HEAD/CHANGELOG.md) — change history.

## Security — read before using

- Windows Integrated Authentication only (no SQL Auth).
- Every destructive action (DROP, TRUNCATE, DELETE, ALTER, etc.) requires explicit confirmation (`confirm: true`) — never executes silently.
- Database discovery (`db_scan_folder`) only scans folders explicitly allowed in `config.toml` (allowlist).
- Full detail in [`docs/SECURITY.md`](https://github.com/hermessilva/LocalDB-MCP/blob/HEAD/docs/SECURITY.md).

## License

[MIT](https://github.com/hermessilva/LocalDB-MCP/blob/HEAD/LICENSE).