Short answer
Claude Code and Codex can both use reusable skills built around a SKILL.md file. The main differences are where each tool stores and discovers skills, how users start them, and which product-specific features surround the shared instructions.
Words used in this guide
- AIPM: a tool that installs and updates reusable AI instructions.
- Package: a named group of files that people can install and update together.
- Workflow: a set of steps used to finish a task.
- Git: a tool that records file changes so people can review or undo them.
What this means
The shared idea
A skill gives an AI tool a reusable job description, steps, examples, and optional resources. Keeping one job per skill makes it easier for both people and agents to choose the right workflow.
The important differences
Claude Code and Codex read skills from their own supported locations and apply their own discovery rules. A skill should avoid product-specific assumptions unless it is intentionally made for one tool. Check each product's current documentation before choosing folders or optional fields.
Sharing across a team
Keep shared skill source in Git, review changes, and state which tools were tested. A package can hold common instructions plus target-specific files when the tools need different layouts.
Simple steps to create and AI agent
- Write one clear task in SKILL.md.
- Keep common instructions free of tool-specific wording.
- Add separate target files only when behavior differs.
- Test the skill in Claude Code and Codex.
- Record the tested tools and publish a new version when behavior changes.
Where to go next
If you want to try this in a real project, start with the install guide, then read how to use AIPM. If you want to share your own workflow, read the publishing guide.
FAQ
Can one SKILL.md work in both Claude Code and Codex?
Often yes, when it contains plain task instructions and uses files both tools can read. Product-specific tools, paths, or commands may need separate guidance.
Does AIPM currently install directly into Codex?
AIPM currently lists Cursor and Claude as supported install targets. Codex-oriented skills can be packaged and documented, but direct Codex installation should not be claimed until that target is supported and tested.