A reader recently highlighted ChemDraft (https://chemdraft.ai).
A lightweight, open-source (Apache-2.0) chemical drawing app for macOS and Windows. It is built around local files and a plugin architecture, with drawing, layout, export, and chemistry tools kept in clear boundaries.
ChemDraft is a vibe coded chemical drawing package for macOS (Apple Silicon) and 64-bit Windows with code on GitHub https://github.com/jgassens/ChemDraft. ChemDraft ships a free agent skill, in the open Agent Skills format, that teaches AI assistants (Claude Code, Claude Desktop with the MCP server, and Codex) to use ChemDraft’s own tools instead of drawing molecules by hand or quoting chemistry numbers from memory.
ChemDraft is built on a number of open-source chemical libraries including RDKIt, Ketcher, Avogadro, OPSIN, InChi and openchemlib.
There is an article in CEN describing ChemDraft, Chemist vibe codes a ChemDraw clone.
Some ChemDraw features aren’t available in ChemDraft, such as ChemDraw’s ability to copy and paste structures to and from Microsoft Word and PowerPoint while maintaining the ability to edit them.