Complete Environment Variable Documentation

[aabrius]

Summary

Document missing environment variables in .env.example for complete configuration reference.

Background

The .env.example file is missing documentation for several environment variables that are used in the codebase:

• CLICKHOUSE_PROXY_PATH
• MCP_SERVER_HOST
• MCP_SERVER_PORT

This makes it harder for users to understand all available configuration options.

Current State

.env.example has basic OAuth and ClickHouse variables documented but is missing advanced configuration options.

Tasks

• Add CLICKHOUSE_PROXY_PATH documentation with example and use case
• Add MCP_SERVER_HOST documentation (advanced OAuth token server config)
• Add MCP_SERVER_PORT documentation (advanced OAuth token server config)
• Add comments explaining when each variable is needed
• Add security notes about credential management
• Mark advanced variables as optional with clear defaults
• Add section headers for better organization (Basic, OAuth, ClickHouse, Advanced)

Proposed Additions

# Advanced Configuration (Optional)
# CLICKHOUSE_PROXY_PATH: Proxy path for ClickHouse connections (optional)
# CLICKHOUSE_PROXY_PATH=/proxy

# OAuth Token Server (Advanced - rarely needed)
# MCP_SERVER_HOST: Host for OAuth token server
# MCP_SERVER_PORT: Port for OAuth token server
# MCP_SERVER_HOST=127.0.0.1
# MCP_SERVER_PORT=8001

Files to Modify

• .env.example

Benefits

• Complete configuration reference for users
• Better onboarding experience
• Reduced support questions about configuration
• Documents all available options

Time Estimate

1 hour

Priority

Medium - Documentation completeness

References

• Review finding: M3 - Environment Variable Documentation Incomplete
• Variables found in: mcp_env.py lines 124-125, 150-151, mcp_server.py lines 182-183