Avanti Fellows PostgreSQL MCP Server

Read-only MCP server for querying the Avanti Fellows DB Service (PostgreSQL).

What is this?

This is an MCP (Model Context Protocol) server that lets Claude Code, Cursor, and other AI tools query our PostgreSQL database directly. It's read-only - no writes allowed.

Available Tools

Tool	Description
query	Run any SELECT query
list_tables	List all tables in the database
describe_table	Get column info, primary keys, foreign keys
sample_data	Get sample rows from a table
count_rows	Count rows with optional WHERE clause
search_columns	Find columns by name across all tables

Installation

1. Install the package

pip install git+https://github.com/avantifellows/mcp-postgres.git

2. Set up credentials

Add these to your shell profile (~/.zshrc or ~/.bashrc):

export AF_DB_HOST="af-database-host"
export AF_DB_PORT="5432"
export AF_DB_USER="your_username"
export AF_DB_PASSWORD="your_password"
export AF_DB_NAME="database_name"

Then reload: source ~/.zshrc

3. Configure your AI tool

Claude Code

claude mcp add avanti-db -- avanti-mcp-postgres

Verify it's working:

claude mcp list

Cursor

Add to ~/.cursor/mcp.json:

{
  "mcpServers": {
    "avanti-db": {
      "command": "avanti-mcp-postgres",
      "env": {
        "AF_DB_HOST": "af-database-host",
        "AF_DB_PORT": "5432",
        "AF_DB_USER": "your_username",
        "AF_DB_PASSWORD": "your_password",
        "AF_DB_NAME": "database_name"
      }
    }
  }
}

Usage Examples

Once configured, just ask Claude/Cursor about the database:

"What tables are in the database?"
"Show me the schema for the students table"
"How many users signed up this month?"
"Find all columns with 'email' in the name"
"What does the enrollment data look like?"

Updating

pip install --upgrade git+https://github.com/avantifellows/mcp-postgres.git

Local Development

# Clone the repo
git clone https://github.com/avantifellows/mcp-postgres.git
cd mcp-postgres

# Create virtual environment
python -m venv venv
source venv/bin/activate

# Install in dev mode
pip install -e .

# Create .env file with credentials
cp .env.example .env
# Edit .env with your credentials

# Test the server
avanti-mcp-postgres

Security Notes

• This server is read-only - INSERT, UPDATE, DELETE are blocked
• Uses your personal database credentials
• Queries are logged locally but not sent anywhere
• Don't commit credentials to git

Troubleshooting

"Connection refused"

• Check that AF_DB_HOST is correct and accessible from your network
• Verify you're on VPN if required

"Authentication failed"

• Double-check AF_DB_USER and AF_DB_PASSWORD
• Ensure your user has SELECT permissions

Server not showing in Claude Code

• Run claude mcp list to check status
• Try removing and re-adding: claude mcp remove avanti-db && claude mcp add avanti-db -- avanti-mcp-postgres