DDC-CI Control Bridge vs DisplayBuddy

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.

DisplayBuddy controls supported external monitor settings from a Mac menu bar or Windows taskbar. Depending on the display, it can adjust brightness, contrast, speaker volume, input source, resolution, and rotation. The Mac app uses DDC for hardware control and can use gamma dimming when a monitor does not respond. The maker says it also controls supported LG webOS and Samsung Tizen smart monitors over Wi-Fi. Users can save presets and synchronize brightness across displays. On Mac, presets can be scheduled by sunrise, sunset, time of day, charger state, or connected display; the app also supports Shortcuts, Siri, a command-line interface, and MCP. The Windows app supports Windows 10 and 11, with presets, hotkeys, input switching, and resolution and refresh-rate controls. Personal costs $24.99, paid once for one Mac, Pro costs $29.99, paid once for up to two Macs, and Family costs $49.99, paid once for up to five Macs; each includes lifetime access. There is no free plan, but a 7-day trial is available. Core controls work offline after internet-based license activation.