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Argos-MCP

A hundred eyes on your databases, and none of them blink.

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Argos Panoptes (Ἄργος Πανόπτης) is the giant of Greek myth with a hundred eyes, set by Hera to guard Io. Only some of his eyes slept at a time, so he was never fully asleep and nothing passed him unseen. Panoptes means "all-seeing".

TL;DR: Argos-MCP lets Claude Code query PostgreSQL, MySQL, SQLite, and SQL Server through one MCP server. It routes each request through validation, access controls, connection adapters, and an audit record before it reaches the database.

The result is multi-database access with strong security defaults, per-query auditing, and support for SSH tunnels. Every query is watched, and nothing reaches your data unlogged.

Status: pre-release. Argos-MCP is not yet published to npm, and the publish step in the release workflow is deliberately dormant. The source is public on GitHub, so install from source (see Quick start). Any npm install -g argos-mcp command you find elsewhere will not resolve yet.

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Why Argos-MCP?

Security First

• SELECT-Only Mode - Production-safe read-only database access
• Query Validation - Bound parameters, stacked statements refused, comment- and literal-aware parsing, complexity limits
• SSH Tunneling - Secure encrypted connections through bastion hosts
• Audit Logging - One record per query: database, statement hash, duration, outcome, never the values

High Performance

• Connection Pooling - Efficient database connection management
• Schema Caching - Captured once per database, reused for the session
• Query Optimization - Built-in performance analysis and recommendations
• Batch Operations - Execute multiple queries with transaction support

Universal Database Support

• PostgreSQL - Full support including advanced features
• MySQL/MariaDB - Via mysql2, including Azure Database for MySQL/MariaDB
• SQLite - Perfect for development and small applications
• SQL Server - Enterprise-grade Microsoft SQL Server support, including Azure SQL with passwordless sign-in through the Azure CLI

Developer Experience

• One-command install - Registers with Claude Code via the native claude mcp add
• TypeScript Native - Full type safety and IntelliSense support
• Comprehensive Docs - Detailed guides, tutorials, and API reference
• Extensive Testing - Unit and integration suites, plus mutation testing on the security-critical paths

Quick start

Requirements: Node.js >= 22 and the Claude Code CLI. Connecting to Azure SQL with authentication=azure-cli additionally needs the Azure CLI on PATH and a completed az login; nothing else does.

1. Build

git clone https://github.com/AraneaDev/Argos-MCP.git
cd Argos-MCP
npm install
npm run build

2. Configure databases

npm run setup

Interactive wizard for adding database connections, security settings, and SSH tunnels. It writes a config.ini, by convention at ~/.config/argos/config.ini, though any path works. You can also add databases at runtime with the sql_add_database tool.

3. Register with Claude Code

claude mcp add argos --scope user -- \
  node "$(pwd)/dist/index.js" --config "$HOME/.config/argos/config.ini"

Scopes:

| Scope | Flag | Where it lives | Use when | |-------|------|----------------|----------| | User | --scope user | ~/.claude.json | You want Argos in every project (most common) | | Project | --scope project | .mcp.json in the repo | You want to share it with your team via git | | Local | (default) | Per-project, private | You're just trying it out |

4. Verify

claude mcp list

You should see argos listed as connected. Its tools appear in Claude Code as mcp__argos__sql_query, mcp__argos__sql_get_schema, and so on.

Removing it

claude mcp remove argos --scope user

Use cases

Data Analytics & Business Intelligence

"Show me the top 10 customers by revenue this quarter, including their growth rate compared to last quarter"

Production Database Monitoring

"Check the status of our user registration system - how many signups in the last 24 hours and any error patterns?"

Database Administration

"Analyze the performance of our product catalog queries and suggest optimizations"

Development & Testing

"Generate test data scenarios based on our current user demographics"

Architecture

graph TB
 Claude[Claude Code] --> MCP[MCP Protocol]
 MCP --> Security[Security Layer]
 Security --> Connection[Connection Manager]
 Connection --> Adapters[Database Adapters]

 Adapters --> PostgreSQL[(PostgreSQL)]
 Adapters --> MySQL[(MySQL)]
 Adapters --> SQLite[(SQLite)]
 Adapters --> MSSQL[(SQL Server)]

 Security --> SSH[SSH Tunneling]
 SSH --> Bastion[Bastion Host]
 Bastion --> RemoteDB[(Remote Database)]

Built on solid foundations:

• TypeScript - Full type safety and modern development experience
• Node.js - Cross-platform compatibility and excellent ecosystem
• MCP Protocol - Standard protocol for AI tool integration
• Industry-standard drivers - Proven database connectivity libraries

Documentation hub

Getting Started

• 5-Minute Quick Start - Get running fast
• Installation Guide - Detailed setup instructions
• First Database Tutorial - Connect your first database
• Claude Integration - Register with Claude Code

Architecture & Design

• System Architecture - How it all works together
• Security Architecture - Defense-in-depth security model
• Database Layer - Adapter pattern implementation

API Reference

• MCP Tools Reference - Complete tool documentation
• TypeScript API - Developer API reference
• Configuration Reference - All configuration options

Advanced Guides

• Multi-Database Setup - Managing multiple databases
• SSH Tunneling - Secure remote access
• Security Hardening - Production security guide
• Performance Tuning - Optimization strategies

Browse All Documentation

Configuration examples

Production PostgreSQL with SSH

[database.production]
type=postgresql
host=internal-db.company.local
port=5432
database=production_app
username=readonly_user
password=secu…[redacted]
ssl=true
select_only=true
timeout=15000

# SSH Tunnel Configuration
ssh_host=bastion.company.com
ssh_port=22
ssh_username=tunnel_user
ssh_private_key=/secure/path/ssh_key
# Required: without a pinned fingerprint the tunnel refuses to connect, rather
# than trusting whatever host key it is offered. Get it from the bastion with
#   ssh-keygen -lf /etc/ssh/ssh_host_ed25519_key.pub
ssh_host_fingerprint=SHA256:47DEQpj8HBSa+/TImW+5JCeuQeRkm5NMpJWZG3hSuFU

[security]
max_joins=5
max_subqueries=3
max_complexity_score=50

Azure SQL without a password

The Azure CLI's own sign-in is the credential, so no secret is written to config.ini at all.

[database.azure_sql]
type=mssql
host=your-server.database.windows.net
port=1433
database=your_database_name
authentication=azure-cli
select_only=true

# Only when the server's tenant is not the CLI's active context, which is the
# usual case for an account with access to several tenants. Must be the GUID.
# azure_tenant_id=00000000-0000-0000-0000-000000000000

Needs az login beforehand, and the signed-in identity mapped as a database user: CREATE USER [you@company.com] FROM EXTERNAL PROVIDER;. Encryption and certificate verification are forced on for this mode, because an access token is a bearer credential and an unverified connection hands it to whoever answers.

See the SQL Server guide for the details, including unattended use.

Multi-Database Analytics Setup

[database.transactions]
type=postgresql
host=transactions-db.company.com
database=transactions
select_only=true

[database.users]
type=mysql
host=users-db.company.com
database=users
select_only=true

[database.analytics]
type=sqlite
file=./data/analytics.sqlite
select_only=false

[database.local_cache]
type=sqlite
file=./data/cache.sqlite
select_only=false
mcp_configurable=true

[extension]
max_rows=1000
query_timeout=30000

Security features

Multi-Layer Security Model

1. Query Validation - SQL injection prevention and syntax analysis
2. Complexity Limits - Prevent resource-intensive queries
3. SELECT-Only Mode - Read-only database access for production safety
4. Connection Encryption - SSL/TLS and SSH tunnel support
5. Audit Logging - Comprehensive security event tracking
6. Field Redaction - Automatic masking of sensitive data in query results

Field Redaction

Automatically mask, replace, or partially obscure sensitive fields (emails, phone numbers, SSNs, etc.) in query results before they reach Claude or other clients. Redaction is configured per-database in config.ini:

[database.production]
type=postgresql
host=prod-db.company.com
database=app_db
username=readonly_user
password=secure_pass
select_only=true

# Field Redaction
redaction_enabled=true
redaction_rules=*email*:partial_mask,*phone*:full_mask,ssn:replace:[PROTECTED]
redaction_case_sensitive=false
redaction_log_access=true

Redaction types: | Type | Example Input | Example Output | |------|--------------|----------------| | partial_mask | john.doe@example.com | j******.e@*****.com | | full_mask | 555-123-4567 | ********** (capped at 10) | | replace | 123-45-6789 | [PROTECTED] | | custom | Regex-based | Custom pattern |

Field patterns: exact match (email), wildcard (`*e