xAI open-sources the Grok CLI coding agent, including a self-contained Rust Mermaid-to-Unicode renderer

Simon Willison's Blog·medium signal

xAI has open-sourced its Grok CLI coding agent, and Simon Willison, digging through the codebase, surfaced xai-grok-markdown/src/mermaid.rs — a self-contained Rust module that renders Mermaid diagrams as Unicode box art in the terminal. The release puts a fourth major-lab terminal coding agent in the open alongside Claude Code's ecosystem, and the Mermaid renderer is independently liftable for any TUI that needs diagram output.