copperhead

copperhead is a command line AI agent for hardware development. From a natural language brief it can run a full pipeline covering spec, architecture, part selection, schematic, first draft layout, gerbers, a firmware scaffold, and a development plan. On an existing project, the copperhead do command operates on the KiCad repository the way a coding agent operates on a codebase.

The agent reads and edits real .kicad_sch and .kicad_pcb files, keeps markdown design documents as memory, propagates a change across all artifacts that reference it, and verifies its own work by running kicad-cli ERC and DRC until the checks pass. Two gates structure the loop: no edit happens without a validated change proposal first, and no change counts as done until the ERC and DRC tools agree.

The README states the project is early, that Phase 1 is implemented and the CLI runs, and that the technical specification is the source of truth, with the surface expected to move before version 1.0. Installation is via npm (npm install -g copperhead), and it needs Node.js 20 or later, KiCad 8 or later, and one model backend (Codex CLI, Cursor Agent CLI, Claude Code, or an Anthropic or OpenAI API key). An MCP server mode is marked experimental.