Codex's runtime cache bundles LibreOffice with Homebrew library dependencies

Willison was clearing disk space with OmniDiskSweeper when he found 1.7GB in ~/.cache/codex-runtimes/codex-primary-runtime, the local runtime cache for the OpenAI Codex desktop app (since rebranded to ChatGPT). Inside: a full Python installation, a full Node.js installation, and native binaries for Poppler, git, and a 429.7MB headless build of LibreOffice. A "documents" skill folder in the same cache tells Codex how to find and use them.

The bundling has a documented failure mode. A June 6 bug report on the Codex GitHub repository (issue #26816) describes that same bundled LibreOffice binary crashing on launch on a Mac without Homebrew installed: the soffice binary is dynamically linked against /opt/homebrew library paths that do not exist outside a Homebrew install, so it fails with a "Library not loaded" error. DOCX generation still works, the reporter noted, but Codex's document visual-rendering and QA step fails until soffice can start, and reinstalling Codex did not fix it.

Why it matters: A coding agent's runtime includes every binary the harness carries to support its features. Each one adds dependencies, disk cost, and machine-specific failure modes. Anyone building or auditing an agent harness should inspect its cache directory alongside the product's stated capabilities.