How to use the same skills in Claude and ChatGPT

Both tools now use the same open skill format: a folder with a SKILL.md file holding a name, a description and instructions. Write the skill once in that format and you can add it to both. The hard part isn't the format. It's keeping two copies identical as the skill changes.

What a skill looks like

A skill is a folder. Inside is a file called SKILL.md that starts with a name and a description, followed by plain-language instructions. It can also hold examples or reference files. The description is what each AI reads to decide when to use the skill, so write it carefully (see why skills don't trigger).

Adding it to Claude for your organization

On Claude Team and Enterprise, skills for the whole organization are managed under Organization settings, in Plugins and skills. Only Owners and Primary Owners can change this page. You can upload a skill directly, which gives it to everyone, or sync a folder of skills from GitHub or GitLab so changes arrive when you update the repository.

Each plugin then gets an availability setting: Required, Installed by default, Available, or Not available. Enterprise can set this per group.

Adding it to ChatGPT for your workspace

On ChatGPT Business and Enterprise, admins manage plugins in the Admin console. They can import a marketplace of skills from GitHub, and ChatGPT accepts the same Claude-compatible format. New plugins start as Available; admins can set them to Installed or Disabled. Imports sync daily, or right away with Sync now. Per-role settings are Enterprise and Edu only.

Where the two differ

Always-on instructions. Claude has Organization preferences, up to 3,000 characters applied to every chat. ChatGPT has no workspace-wide equivalent, so brand rules need to live in a skill.
When updates arrive. Claude syncs when the repository changes, which can take up to 30 minutes. ChatGPT checks daily unless an admin presses Sync now.
Removing a skill. In ChatGPT a plugin removed from the repository stays listed as "No longer in source" until an admin disables it.

Keeping the copies in step

Most teams start by pasting the same text into a Claude Project and a Custom GPT. Within a month the two have drifted. To avoid that:

Keep one master copy of each skill, not one per tool.
Publish both tools from that master copy, never edit inside a tool.
Give every change a version number and a note saying what changed.
Check that both tools show the new version after each change.
Test the description in both tools, since each picks skills a little differently.