How Codex, Claude, and Gemini Are Battling for the Desktop AI Market

CLI remains programmers' favorite, but expanding market share now requires desktop clients; Claude, Gemini, and Codex each have their own apps.

Gemini

Gemini excels at quick Q&A and information gathering. Its biggest advantage is its tiny size—under 200 MB, which on a 256 GB M4 machine forces use of the web version.

Daily use relies on a shortcut to Mini Chat mode, then closing after answering.

Key useful points:

Integration with the Google ecosystem, seamless handoff to Notebook LM.

Screen sharing: any open file, webpage, or content can be fed to Mini Chat for dialogue.

Image generation: Nano Banana provides fast image, video, and music creation comparable to OpenAI’s Image 2.

Codex

Codex has become more usable, fixing many earlier pain points such as opening intermediate or final artifacts quickly.

File‑tree browsing is now convenient, allowing easy project file navigation and adding files or folders to a conversation.

Preview supports various file types (PDF, spreadsheets, presentations, documents, images).

Built‑in browser lets you annotate pages and issue commands directly, turning the page into an interactive interface.

Codex can invoke gpt-image-1.5 to generate and iterate images.

Voice input is now supported.

Browser automation can pop up and act on pages without extra explanation.

Computer control: visual recognition, clicking, typing let Codex operate applications on your Mac, and multiple agents can run in parallel without interrupting other work.

Limitation: the author's IP does not support this feature.

Conversation feature keeps temporary chats from polluting projects.

Pro‑only “Chronicle” feature (unavailable to Plus users) uses screen context to build memory: it runs silently, periodically captures screen content, extracts memory entries, and recalls recent context in new threads.

Chronicle stores unencrypted markdown files in ~/.codex/memories_extensions/chronicle/.

Drawbacks:

Rapid consumption of rate limits due to background agents.

Screen captures are stored locally for only six hours before automatic deletion.

Memory files are unencrypted markdown.

Potential prompt‑injection risk if a malicious webpage is opened.

Codex also includes a humorous “Absolutely” theme referencing Claude.

The plugin system now exceeds 100 plugins, and users can create and manage their own plugins easily.

Personal note: the author has not used Claude Code for a long time; Claude Opus 4.7 in Copilot feels frustrating, while the Codex desktop client feels smooth and powerful, strongly recommended.