Sequel

MCP server for Claude that connects to MySQL, MariaDB, PostgreSQL, and SQLite databases. Query your databases using natural language. Supports multiple named connections, SSH tunnels, readonly mode, and per-connection row limits.

Install & Registration

Tip: ask Claude to read this README and set up the server for you.

Option 1: uvx (recommended) — no installation needed, always runs the latest version:

claude mcp add mcp-sequel uvx mcp-sequel

Option 2: from cloned repository:

git clone https://github.com/eukos/mcp-sequel
claude mcp add mcp-sequel uv run --directory /path/to/mcp-sequel mcp-sequel

Configuration

Tip: ask Claude to read this README and create a connection config for you.

One file per connection in ~/.config/mcp-sequel/. The filename (without .json) becomes the connection name.

~/.config/mcp-sequel/
├── production.json
├── staging.json
└── local.json

Each file is one connection. Examples:

MySQL / MariaDB

{
  "type": "mysql",
  "host": "db.example.com",
  "port": 3306,
  "user": "analyst",
  "password": "secret",
  "database": "myapp",
  "readonly": true,
  "row_limit": 1000,
  "description": "Production replica, analytics only"
}

Field	Required	Default	Description
type	yes	—	"mysql" or "mariadb"
host	yes	—	hostname or IP
user	yes	—	database user
password	yes	—	database password
port	no	3306	TCP port
database	no	—	default database; can be overridden per query
readonly	no	true	if true, only SELECT/SHOW/DESCRIBE/EXPLAIN are allowed
row_limit	no	1000	max rows returned; null for no limit
description	no	—	human-readable label shown in list_connections
ssh_tunnel	no	—	SSH tunnel config (see below); routes the connection through a bastion host

MySQL via SSH tunnel

Use ssh_tunnel when the database is only reachable through a bastion/jump host. host and port in the top-level config refer to the DB as seen from the SSH server (commonly localhost).

With a key file (most common):

{
  "type": "mysql",
  "host": "localhost",
  "port": 3306,
  "user": "reader",
  "password": "secret",
  "database": "myapp",
  "ssh_tunnel": {
    "host": "bastion.example.com",
    "user": "ubuntu",
    "key_file": "~/.ssh/id_rsa"
  }
}

With an SSH password:

{
  "type": "mysql",
  "host": "localhost",
  "port": 3306,
  "user": "reader",
  "password": "secret",
  "ssh_tunnel": {
    "host": "bastion.example.com",
    "user": "ubuntu",
    "password": "sshpass"
  }
}

Field	Required	Default	Description
host	yes	—	SSH server hostname or IP
user	yes	—	SSH username
key_file	no*	—	path to private key file (~ expanded)
password	no*	—	SSH password (if not using key file)
port	no	22	SSH server port

* at least one of key_file or password should be provided.

PostgreSQL

{
  "type": "postgresql",
  "host": "db.example.com",
  "port": 5432,
  "user": "analyst",
  "password": "secret",
  "database": "myapp",
  "readonly": true,
  "row_limit": 1000,
  "description": "Production PostgreSQL"
}

Field	Required	Default	Description
type	yes	—	"postgresql"
host	yes	—	hostname or IP
user	yes	—	database user
password	yes	—	database password
port	no	5432	TCP port
database	no*	—	database to connect to; can be passed per query instead
readonly	no	true	if true, connection is opened in read-only mode (DB-level enforcement)
row_limit	no	1000	max rows returned; null for no limit
description	no	—	human-readable label shown in list_connections
ssh_tunnel	no	—	SSH tunnel config (same format as MySQL)

* database must be provided either in the config or per query — PostgreSQL requires a database to connect.

SQLite

{
  "type": "sqlite",
  "path": "/data/analytics.db",
  "readonly": true,
  "row_limit": 1000,
  "description": "Local analytics database"
}

Field	Required	Default	Description
type	yes	—	"sqlite"
path	yes	—	absolute path to the .db file
readonly	no	true	if true, opens connection with ?mode=ro (OS-level enforcement)
row_limit	no	1000	max rows returned; null for no limit
description	no	—	human-readable label shown in list_connections

Set permissions to owner-only:

chmod 600 ~/.config/mcp-sequel/*.json

Usage

After registering, restart Claude to load the server. Then try:

• "List available database connections"
• "Show databases for staging"
• "How many customers do we have on production?"
• "Show me the schema of the orders table"
• "Query local: SELECT * FROM users LIMIT 10"
• "Query production: show me the top 10 users by order count"

License

MIT