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Gemini CLI vs Codex CLI

Side-by-side comparison of Gemini CLI and Codex CLI for SKILL.md agent skills — install model, shell access, native support, skill count and best use cases.

Comparison

At a glance

DimensionGeminiCodex
VendorGoogleOpenAI
Native SKILL.md supportVia compatibility layerYes
Verified skills indexed545
Install modelLocal folderLocal folder
Shell / Bash accessYesYes
TaglineGoogle's coding agent CLI with a SKILL.md compatibility layer.OpenAI's coding agent CLI. Adopted the SKILL.md spec verbatim in Dec 2025.

Both

5

Skills verified to work on both Gemini and Codex.

Only Gemini

0

Indexed for Gemini CLI but not yet verified on Codex CLI.

Only Codex

40

Indexed for Codex CLI but not yet verified on Gemini CLI.

Verdict

Which should you pick?

Codex CLI is the deeper SKILL.md target — native support, the broadest verified skill ecosystem, and the closest fit for skill-driven workflows. Gemini CLI works well when you are already invested in the Google ecosystem or need its specific integrations.

Many teams use both — Skills with the SKILL.md spec are portable, and 5 of the skills indexed here are verified on both agents. Browse the per-agent rankings to see which Skills lead on each platform: Skills for Gemini CLI · Skills for Codex CLI.

FAQ

Common questions

Which is better for SKILL.md skills, Gemini CLI or Codex CLI?

Codex CLI has native SKILL.md support; Gemini CLI uses a compatibility layer. Gemini CLI has 5 verified skills indexed here; Codex CLI has 45. 5 skills work on both.

Can I use the same Skill on Gemini CLI and Codex CLI?

5 of the skills indexed here work on both. The SKILL.md spec is shared, so most skills run cleanly on both — the exceptions are skills that depend on agent-specific tools (Bash, Workflows, MCP patterns).

How do I install a Skill on Gemini CLI?

Drop the folder under `~/.gemini/skills/` for user-wide or `.gemini/skills/` for project-scoped. The compatibility layer translates SKILL.md frontmatter automatically.

How do I install a Skill on Codex CLI?

Drop the Skill folder under `~/.codex/skills/` for user-wide or `.codex/skills/` for project-scoped. Codex loads SKILL.md the same way Claude Code does.

Which agent should I pick for cross-platform skill use?

If native SKILL.md support and the broadest skill ecosystem matter most, pick Codex CLI. Gemini CLI works for teams already invested in that platform.

More comparisons

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