DDC-CI Control Bridge vs Lunar

DDC-CI Control Bridge is a free project for controlling compatible monitors through DDC/CI. It can manage brightness, contrast, power, and input, and offers command-line or API access. Its Model Context Protocol server provides resources and tools for AI or agent integration, including reading and writing VCP codes, setting brightness from 0 to 100, and rescanning monitors and capabilities. An MQTT client connects it to automation systems. Listed integrations include Home Assistant auto-discovery, openHAB, Node-RED, Domoticz, and generic MQTT platforms. The project is available as an npm package or as standalone executables for Windows, Linux, and macOS. MCP can run locally over stdio or provide remote HTTP/SSE access to other machines on a network. Authentication requires the DDC_API_KEY environment variable. The project is MIT licensed and invites contributions through GitHub issues or pull requests. A monitor must support DDC/CI with the feature enabled in its on-screen settings. On Linux, access may require i2c-dev and membership in the i2c group. Some VCP codes are read-only, and supported codes vary by monitor.

Lunar is a macOS app for controlling monitors, including external monitor brightness, volume and input. On compatible monitors it uses DDC to send brightness and input commands directly. Manual Mode provides hotkeys for external-monitor adjustments, while Sync Mode copies the MacBook’s adaptive brightness changes to external displays. Sensor Mode adjusts brightness and contrast using an external ambient light sensor; Location Mode responds to the sun’s position. Clock Mode schedules changes by time or by sunrise, noon or sunset. Pro features include XDR Brightness, sub-zero dimming, Auto BlackOut, BlackOut and FaceLight. Lunar also works with macOS Shortcuts and includes a command-line interface for monitor automation. It supports macOS 11 and later and runs natively on Apple Silicon and Intel. When DDC is unavailable, Gamma can dim a display but cannot change its volume or input. The free version permits 100 Manual Mode adjustments and 100 Shortcuts action calls per day. Lunar Pro costs $23.00 USD as a lifetime license.