AdoMcp

AdoMcp

AdoMcp is a Model Context Protocol (MCP) server that helps large language models (LLMs) understand database structure, read table comments, and execute SQL queries.

AdoMcp 是一个基于 Model Context Protocol (MCP) 的数据库工具服务，帮助大型语言模型（LLM）理解数据库结构、读取表注释、执行 SQL 查询。

MCP Tools

| Tool | Description | |---|---| | list_connections | List configured database connections | | add_connection | Add (or replace) a database connection at runtime | | remove_connection | Remove a dynamically-added connection | | list_objects | List database objects (table/view/procedure/function/trigger/sequence/synonym, etc.) | | get_table_schema | Get table schema details (columns/types/nullability/PK/default/comments) | | get_table_indexes | Get table indexes | | query_sql | Execute read-only SQL and return CSV | | execute_sql | Execute write SQL (requires --allow-any-sql) |

Recommended Tool Workflow (for LLM agents)

To reduce mistakes (wrong database/schema/object), use tools in this order:

1. list_connections to discover available connections.
2. If none are available, call add_connection.
3. Before inspecting a table/view, call list_objects to locate schema + objectType + objectName.
4. Use get_table_schema for column details (type, nullability, PK, default, comments).
5. Use get_table_indexes when index/key design matters.
6. Use query_sql only for read-only verification.
7. Use execute_sql only when explicitly authorized and server is started with --allow-any-sql.

Oracle note: objects without owner prefix may be synonyms. Always confirm the real schema via list_objects first.

Supported Databases

| Database | Driver | Comment support | |---|---|---| | SQL Server | Microsoft.Data.SqlClient | MS_Description extended properties | | MySQL / MariaDB | MySqlConnector | TABLE_COMMENT / COLUMN_COMMENT | | PostgreSQL | Npgsql | obj_description / col_description | | SQLite | Microsoft.Data.Sqlite | — (SQLite has no native comments) | | Oracle | Oracle.ManagedDataAccess.Core | ALL_TAB_COMMENTS / ALL_COL_COMMENTS (includes PUBLIC synonyms) |

ORM support: Dapper · SqlSugarCore

Requirements

• .NET 10 SDK

---

Quick Start

1. Configure database connections (optional)

Edit src/AdoMcp/appsettings.json and add pre-configured connections under the Databases array. You can also skip this step entirely and let the LLM add connections dynamically via the add_connection tool.

"Databases": [
  {
    "Name": "mydb",
    "DbType": "SqlServer",
    "ConnectionString": "Server=localhost;Database=MyDb;User Id=sa;Password=***;TrustServerCertificate=true;",
    "Description": "Main business database"
  }
]

Supported DbType values: SqlServer | MySql | PostgreSql | Sqlite | Oracle

> Security tip: Use .NET User Secrets or environment variables to manage connection strings in production.

2. Run the server

Automatic mode detection (recommended)

When stdin is redirected (i.e. launched by an MCP client), stdio mode is used automatically. When run interactively in a terminal, HTTP/SSE mode is used automatically.

dotnet run --project src/AdoMcp

Specify mode manually

# stdio mode (all logs go to stderr; stdout carries only MCP JSON-RPC)
dotnet run --project src/AdoMcp -- --stdio

# HTTP/SSE mode (default: http://localhost:5100, MCP endpoint /mcp)
dotnet run --project src/AdoMcp -- --http

# Via environment variable
ADOMCP_MODE=http dotnet run --project src/AdoMcp

Enable execute_sql (write operations)

By default the execute_sql tool is disabled to prevent unauthorised writes. Add --allow-any-sql to enable it:

dotnet run --project src/AdoMcp -- --allow-any-sql
# Combine with transport mode
dotnet run --project src/AdoMcp -- --http --allow-any-sql

3. Run via NuGet / dnx (.NET 10)

After the package is published to NuGet.org, you can run it without cloning the repo:

# Install as a global .NET tool once, then run directly
dotnet tool install -g AdoMcp
adomcp

# Or use dnx (.NET 10+) — installs and runs on demand
dnx AdoMcp
dnx AdoMcp -- --allow-any-sql

---

Dynamic connections at runtime (no config file needed)

LLMs can add new database connections during a session using add_connection:

User: Connect me to Oracle database oradb01
LLM → calls add_connection(
    connectionString = "Data Source=oradb01:1521/PROD;User Id=appuser;Password=***;",
    dbType = "Oracle",
    name = "prod-oracle",
    description = "Production Oracle DB"
)
→ returns: Connection 'prod-oracle' (Oracle) added successfully.
LLM → calls list_objects(connectionName = "prod-oracle")

Dynamically-added connections exist only for the lifetime of the process; restart the server or add the connection to appsettings.json for persistence.

---

Via dnx (after NuGet publish)

{
  "mcpServers": {
    "adomcp": {
      "command": "dnx",
      "args": ["-y","AdoMcp"]
    }
  }
}

HTTP mode

Start the server first:

dnx -y AdoMcp -- --http

Then configure the client:

{
  "mcpServers": {
    "adomcp": {
      "url": "http://localhost:5100/mcp"
    }
  }
}

---

Environment variables

All environment variables are prefixed with ADOMCP_ (override appsettings.json):

| Variable | Description | |---|---| | ADOMCP_MODE | Transport mode: stdio or http (auto-detected when not set) | | ADOMCP_URLS | HTTP listen address, e.g. http://0.0.0.0:5100 |

---

MCP Registries

Official MCP Registry

This repository now includes server.json for the official MCP Registry with the server name io.github.John0King/adomcp.

To publish to the official MCP Registry:

1. Publish the NuGet package AdoMcp to NuGet.org.
2. Push a version tag such as v1.0.1, or manually run the Publish to NuGet and MCP Registry GitHub Actions workflow.
3. The workflow publishes the NuGet package, authenticates with GitHub OIDC, and publishes server.json to the MCP Registry.

Build & Pack

# Build
dotnet build

# Pack as a NuGet tool (supports dnx)
dotnet pack src/AdoMcp -c Release -o ./nupkg

# Publish to NuGet.org (set NUGET_API_KEY first)
dotnet nuget push ./nupkg/AdoMcp.*.nupkg --source https://api.nuget.org/v3/index.json --api-key $NUGET_API_KEY

Source & license

This open-source MCP server is cataloged on AgentStack and links to its original source — we do not rehost the code.

• Author: John0King
• Source: John0King/AdoMCP
• License: MIT

Install and usage instructions live in the source repository linked above.