Short answerWith OpenAI's migration, instructions become a skill and knowledge files become reference files. Custom actions, the selected model, conversation starters, previous chats and capability settings do not carry over one-to-one.
Transfer matrix (OpenAI plugin migration)
| Part of your GPT | What happens |
|---|---|
| Instructions | Become a skill |
| Knowledge files | Come over as the skill's reference files |
| Connected apps | Remain part of the plugin |
| Custom actions | Do not transfer; rebuild with an app or custom MCP server |
| Selected model | Does not transfer; workspace defaults apply |
| Conversation starters | May not copy one-to-one |
| Previous chats | May not copy |
| Capability settings | Not guaranteed to give the same tools or behavior |
Source: OpenAI's migration guide, checked October 18, 2026. Other platforms differ; check each one's documentation.
If you rebuild elsewhere
Treat everything except instructions and files as something to recreate. Starters and descriptions are easy to rewrite, Actions are not; see Actions migration and conversation history.
Check your GPT before you move it
Paste your instructions, file names and Actions schema into the free checker. It runs in your browser and builds a portable bundle. Nothing is uploaded.
Open the free checkerRelated guides
Sources
Pages describing other companies' products reflect their public documentation on the date shown and can go out of date.