DDC-CI Control Bridge vs ddcctl

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.

ddcctl is a free GPLv3 open-source command-line utility for adjusting external monitor controls from the macOS shell. Its primary controls are brightness and contrast. Depending on monitor firmware, it may also switch input source, change built-in speaker volume or RGB colors, select color presets, and reset settings. The stated scope is macOS, Macintosh hardware, and DDC-controlled monitors. Installation is available through Homebrew, downloadable release binaries, or a source build; building requires Xcode and running make. Example scripts can be invoked by Alfred, ControlPlane, or Karabiner to switch presets. The project describes itself as a personal utility in maintenance mode and asks users to debug their own issues. Its maker says there is no time to triage new issues or support non-bugs, and no support or discussion forum is planned. Verification is manual, with no CI connected to real Macs and monitors. The releases page lists v1 as the latest release. The listed controls include DDC/CI, input switching, and command-line access.