Free tool
Turn a custom GPT into a skill
Custom GPTs stop working on 11 December 2026. Paste your GPT's name, instructions, and conversation starters, and you get a SKILL.md that keeps the GPT's behavior and runs in ChatGPT, Claude, and coding agents. It's free, and nothing leaves your browser.
Your GPT in, a skill out
In ChatGPT, open your GPT, click Edit GPT, then the Configure tab. Copy each field from there.
JavaScript is off, so here is the same job by hand:
- Make a folder named after your GPT in lowercase with hyphens, such as
proposal-reviewer. - In it, make a file named
SKILL.mdthat starts with three hyphens,name: proposal-reviewer,description: "What the GPT does. Use when …", and three hyphens again. - Under that, paste the GPT's instructions, then a list of its conversation starters as example requests.
- Put any Knowledge files in the same folder and name them in the instructions.
Next: share it with your team on AI Skill Pod
A GPT link used to reach anyone you sent it to. AI Skill Pod gives your skill one pod and one invite link: teammates and clients connect Claude, ChatGPT, Claude Code, Codex, Cursor, or OpenCode through one MCP link, and personal emails are welcome. In ChatGPT that works on Pro, Business, and Enterprise through a custom MCP connector or developer mode, and on other plans where the plan allows custom connectors.
What carries over from a GPT, and what doesn't
| GPT part | In the skill |
|---|---|
| Name | The skill's name, in lowercase with hyphens |
| Description | The start of the skill's description, followed by when to use it |
| Instructions | The body of SKILL.md, as written |
| Conversation starters | "Example requests" in the body, and the trigger words in the description |
| Knowledge files | Paste what matters into the instructions: AI Skill Pod keeps only SKILL.md. For Claude or a coding agent you can also put the files next to SKILL.md; the converter adds a line telling the AI to read them |
| Actions | Not carried over. OpenAI's FAQ says actions need rebuilding as a connector or a custom MCP server |
| Model choice | Not carried over: whoever uses the skill picks their own model |
Why a skill instead of a ChatGPT plugin
OpenAI's own migration turns a GPT into a ChatGPT plugin, with the instructions inside as a skill. That plugin lives in ChatGPT only. A SKILL.md file follows the open Agent Skills format, so the same file also runs in Claude, Claude Code, Codex, Cursor, and OpenCode. Your teammates and clients can keep the AI they already use.
For the whole move, from saving your GPT to sharing it again, read Custom GPTs retire on 11 December: how to keep sharing yours.
Sources
- OpenAI Help: Custom GPT retirement and migration FAQ (read 2026-11-04)
- Agent Skills specification (read 2026-11-04)
- Anthropic: Skill authoring best practices (read 2026-11-04)