Install Codeck in Codex: creating Markdown presentations on Mac

The new feature is a presentation workspace inside Codex

This Codeck is by Łukasz Kuczborski, with the official repository lkuczborski/Codeck. It combines Markdown source, slide previews and AI iteration in one presentation workflow. Do not install a same-named project by another author based only on search results, or treat the author's marketplace as OpenAI's public plugin catalog.

The plugin distribution branch was first committed on October 3, 2026 and subsequently updated to 0.3.8. Public notarization records show Accepted. It provides a separate sidebar workspace in Codex desktop and supports iterating on a presentation through the native composer. These dates are UTC. This article reviewed public material on October 4, Beijing time; it did not run the plugin on a Mac or reproduce the author's demonstration.

Choose the Codex plugin or standalone Mac app

Choose the plugin to write and present inside Codex. The current prebuilt package requires an Apple Silicon Mac with macOS 14 or later. Intel users can build it themselves following the author's instructions, but cannot directly use that prebuilt package. The plugin does not require the standalone Codeck app to be installed or running. Windows and Linux are unsupported.

For a separate presentation app, download Codeck-v0.7-macos-universal.zip from the author's Releases, extract it and move Codeck.app to Applications. This standalone app supports Apple Silicon and Intel, also requiring macOS 14 or later. Version 0.7 was released on October 2; its release notes say it is signed and notarized and can use the executable bundled with Codex desktop. It is not the installer for plugin 0.3.8.

Confirm Codex host and sign-in requirements before installation

The separate sidebar workspace requires Codex desktop with workspace extensions support. The author does not specify an exact minimum desktop version, so verify that the current host has the required capability. The CLI must support codex plugin. Loading skills and MCP tools in the CLI alone does not automatically provide a desktop sidebar.

Terminal installation also requires available codex and Git commands and access to the public GitHub repository. Live cards and AI iteration require valid Codex sign-in and networking. The prebuilt plugin includes its local helper, so users do not need Swift, Node, npm or a separately configured OpenAI API key. That does not promise subscription-free use, free calls or unlimited quota.

Before starting, record the operating system, chip type and Codex version, and confirm the terminal account matches the normal desktop environment. The author's documentation does not list a complete plan-eligibility matrix. If an organization restricts custom plugins, establish permitted usage through its existing management process first.

Add the marketplace, then install Codeck

Run two commands in order in a terminal on a Mac meeting the requirements. First add the author's catalog: codex plugin marketplace add lkuczborski/Codeck. Then install the plugin: codex plugin add codeck@codeck-plugins. Keep the repository owner and catalog names exactly as written.

Restart Codex desktop and open Codeck in the sidebar. Alternatively, add only the marketplace, restart the desktop app, choose Codeck Plugins under Plugins, then open Codeck to install it. A new chat can also use @Codeck. With default settings, the CLI and desktop app on the same Mac share the installation; different CODEX_HOME values or profiles may remain separate.

The repository manifest points to the prebuilt package on the codex/plugin-distribution branch, whose public branch and version manifest already exist. Normal installation does not require cloning source, downloading CI artifacts or executing release scripts. Merging source and publishing a plugin are separate actions: a new main-branch commit does not prove an installed plugin has immediately updated.

Use three slides to verify editing, saving and presentation

Start with a three-slide presentation containing a title, key points and a conclusion, or use the native file picker to open an existing .mdeck, .md or .markdown file. Edit one phrase in split view and confirm the preview updates, then drag one thumbnail to check slide ordering. These are suggested first-use steps, not a guarantee based on testing the plugin.

Use Save or Command-S to write the presentation file, record its location and reopen it to check the change. Retaining an automatic draft and writing to the target file are different actions; keep a separate copy before a real presentation. Present starts full-screen playback from the current slide. Check titles, body text and images, then press Esc to exit before editing again.

For initial Codex assistance, ask only for wording changes on one slide and check the changes against the original meaning. Users still need to verify figures, citations and conclusions. Prefer local image assets: the plugin documentation says it does not automatically fetch external image URLs. Visible text does not establish that all images are ready.

Live cards run, but their results need separate preservation

A codex code fence in Codeck can act as a live card, controlled with Run and Stop in preview or full-screen mode. It uses the installed Codex executable and existing sign-in; the standalone app and plugin share the relevant runtime logic. First confirm connectivity with a short prompt containing no sensitive material before using it in a real presentation.

Live results stream into the slide without directly rewriting Markdown. They persist only for the current session and reset when the plugin helper restarts. Review important output and incorporate it into the saved document. Prepare verified static text before presenting so a required conclusion does not depend entirely on one live request.

Troubleshoot a missing sidebar, inactive cards or save failures

If the catalog is missing, run codex plugin marketplace list, confirm codeck-plugins is registered and restart the desktop app. If installation produces no workspace, confirm the plugin is enabled and host capabilities meet requirements, then inspect codeck-workspace MCP startup errors. Loaded skills alone do not prove the local helper started. The author also offers an entry for hosts without workspace extensions: request Open the Codeck presentation workspace in a new chat to try opening the editor. This does not guarantee a separate sidebar. Preserve exact errors before diagnosis rather than repeatedly changing several settings at once.

If a card does not run, check the Codex executable, sign-in, network and whether the selected model is available to the account. Confirm a normal Codex request succeeds before trying one card. Do not treat authentication, quota or model-permission errors as networking failures, or repeatedly trigger the same generation task as an immediate troubleshooting step.

For file-authorization or disk-conflict errors when saving, protect the current draft first. Reselecting a file through the native Open panel can renew file access authorization. If the disk copy changed externally, compare both versions before reloading or saving a separate copy. Do not delete the draft directory just to dismiss an error or grant the plugin access to the entire disk.

Restart after updates and keep your presentation files

The author's explicit update sequence is codex plugin marketplace upgrade codeck-plugins, followed by codex plugin add codeck@codeck-plugins, then restarting the desktop app or opening a new CLI session. The documentation does not guarantee automatic plugin-level updates for personal-repository installations. Refreshing a webpage does not establish that the local version changed.

To uninstall, run codex plugin remove codeck@codeck-plugins. Presentation files and persistent drafts live outside the plugin package, so this procedure does not also remove them. Keep separate copies of important work. After every upgrade, use a small presentation to recheck previews, saving and card behavior before continuing production work.