Agent-to-Body Interfaces Around the Model Hardware Standard: A 47-Day Landscape

Coding agents became everyday developer tools within a year, yet they live almost entirely in the terminal. This article asks who is connecting agents to physical machines, how, and where nobody is. We frame three falsifiable questions (occupancy, vendor entry, felt gap), answered with an open evidence log of 176 dated, source-linked entries from a 90-day window around Anthropic’s Model Hardware Standard announcement of 27 August 2026. The model layer and the program-level SDK layer are full, the ROS world has been aggregated by one MCP server, and among the three agent vendors only Anthropic has announced a standard layer. A sample of 48 developer reports shows the pain is in the driver layer (serial ports, firmware, SDK versions), not in the absence of a bridge. One cell of the brain × body × interface grid, agent × low-cost body × general interface, is crowded with experiments and empty of adoption: twelve occupants, one platform-shaped, none interoperating. It is also the cell the MHS announcement names as the standard’s next phase, with Hugging Face and Raspberry Pi as early adopters [E081]. We close with three events checkable within twelve months, and release the evidence log, classification table and figure data.