Overview

Database Credential Security is a documentation skill that teaches how to manage database credentials securely using MGC Blackbox. Supports MySQL, PostgreSQL, SQLite, MariaDB and other databases. It enables AI agents to execute database operations without ever exposing database passwords or connection strings to the AI model.

This skill contains no executable code and is safe for automatic approval.

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What This Skill Enables

After reading this documentation, an AI agent will understand how to:

• Store database credentials (MySQL, PostgreSQL, SQLite, MariaDB, etc.) securely in MGC Blackbox
• Retrieve credentials at runtime without AI seeing plaintext
• Execute database queries through local scripts
• Manage multiple database connections safely
• Rotate credentials without code changes

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Prerequisites

1. Install MGC Blackbox: pip install mgc-blackbox
2. Start MGC service: mgc (runs at http://127.0.0.1:57219)
3. Token file: ~/.mgc/database/mgc_black_box/.mgc_token

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Storing Database Credentials

Step 1: Prepare Credential File

Create a JSON file containing your database connection details:

{
  "host": "localhost",
  "port": 3306,
  "database": "my_database",
  "user": "db_user",
  "password": "your_password"
}

Step 2: Store in MGC

Important: Use MCP tools for AI agents. CLI may have port conflicts in some environments.

Recommended: MCP Interface

• Use mgc_save MCP tool to store credentials
• Use mgc_get MCP tool to retrieve credentials

Alternative: CLI (for local development only)

mgc_save info_type=config info_owner=my_database < credentials.json

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Database Credential Pattern (Conceptual)

Local Script Pattern

A secure database script follows this pattern:

1. Retrieve credentials from MGC (not visible to AI)
2. Connect to database (using retrieved credentials)
3. Execute queries (using connection)
4. Return results (non-sensitive data only)

The script must never print or expose database credentials.

Conceptual Code Structure

function execute_query(sql):
    credentials = retrieve_from_mgc("my_database")
    connection = connect(credentials)
    result = connection.execute(sql)
    connection.close()
    return result

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MGC Blackbox API Reference

Service Endpoint

• Base URL: http://127.0.0.1:57219
• Token File: ~/.mgc/database/mgc_black_box/.mgc_token
• Token: String token read from token file, required for all API calls

Get Credentials API

Endpoint: /api/mgc/sensitive/get Method: POST Headers:

• X-MGC-Token: (string token read from token file)
• Content-Type: application/json

Body fields:

• info_type: "config"
• info_owner: your chosen identifier

Response fields:

• code: status code
• data.content: JSON string containing stored credentials

Save Credentials API

Endpoint: /api/mgc/sensitive/save Method: POST Headers: same as above

Body fields:

• info_type: "config"
• info_owner: your identifier
• content: JSON string of credentials

Tip: Users can also store credentials manually via MGC WebUI at http://127.0.0.1:57218/skill

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Security Best Practices

1. Never embed credentials in code
2. Use MGC for credential storage
3. Retrieve credentials at runtime only
4. Never log or print credentials
5. Rotate credentials regularly
6. Use separate credentials per database

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Common Patterns

Python Database Connection (Conceptual)

import mysql.connector

def get_connection(credentials):
    return mysql.connector.connect(
        host=credentials["host"],
        port=credentials["port"],
        database=credentials["database"],
        user=credentials["user"],
        password=credentials["password"]
    )

def execute_query(sql):
    creds = retrieve_from_mgc("my_mysql")
    conn = get_connection(creds)
    cursor = conn.cursor()
    cursor.execute(sql)
    result = cursor.fetchall()
    cursor.close()
    conn.close()
    return result

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Use Cases

• Database administration scripts
• Automated backup operations
• Data migration tools
• Application database access
• Multiple environment management (dev/staging/prod)

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License

MIT