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Public story · 2026-07-16 · high
Grok CLI's release makes four major-lab terminal coding agents open source, Simon Willison notes, and one file is meant to be copied elsewhere.
Why now: Willison flagged the module on July 16, the same post that puts the count of open, major-lab terminal coding agents at four.
xAI open-sourced Grok CLI on July 16, making it the fourth major-lab terminal coding agent now in the open, per Simon Willison.
Willison's post frames that as the bigger point: Grok CLI's arrival brings the count of open-source, major-lab terminal coding agents to four.
The specific find is a file: xai-grok-markdown/src/mermaid.rs. It's a self-contained Rust module that renders Mermaid diagrams as Unicode box art directly in the terminal.
Willison says the module is liftable on its own. A developer building a different TUI wouldn't need the rest of Grok CLI, just this file, to get diagram rendering working. For anyone shipping a terminal tool, that's one rendering problem already solved.
The mermaid.rs file will probably get copied into more terminal projects than anyone builds directly on top of Grok CLI itself. A tight, dependency-free utility travels faster than a full coding agent stamped with someone else's opinions. That's the kind of file that outlives the project it shipped in.
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Simon Willison released Datasette / Shared entities / Same source domain / Earlier coverage / Tension
Linked by a graph relationship (Simon Willison released Datasette); both cover Simon Willison, Willison; reported by the same outlet (simonwillison.net).
Simon Willison released LLM / Shared entities / Same source domain / Earlier coverage
Linked by a graph relationship (Simon Willison released LLM); both cover Simon Willison, Willison; reported by the same outlet (simonwillison.net).
Linked by a graph relationship (Simon Willison released LLM); both cover Simon Willison, Willison; reported by the same outlet (simonwillison.net).
Simon Willison released Datasette / Shared entities / Same source domain / Earlier coverage
Linked by a graph relationship (Simon Willison released Datasette); both cover Simon Willison, Willison; reported by the same outlet (simonwillison.net).
Simon Willison uses Claude Code / Shared entities / Same source domain / Earlier coverage
Linked by a graph relationship (Simon Willison uses Claude Code); both cover Simon Willison, Willison; reported by the same outlet (simonwillison.net).
Simon Willison uses Claude Code / Shared entity: Willison / Same source domain / Shared topic / Earlier coverage
Linked by a graph relationship (Simon Willison uses Claude Code); both cover Willison; reported by the same outlet (simonwillison.net).
Simon Willison uses Claude Code / Shared entities / Same source domain / Shared topic / Earlier coverage
Linked by a graph relationship (Simon Willison uses Claude Code); both cover Simon Willison, Willison; reported by the same outlet (simonwillison.net).
Simon Willison released LLM / Shared entity: Simon Willison / Same source domain / Shared topic / Earlier coverage
Linked by a graph relationship (Simon Willison released LLM); both cover Simon Willison; reported by the same outlet (simonwillison.net).