Short answerOpenAPI is a standard way to describe a web service: its address, what you can ask it and what it returns. A GPT Action is defined by an OpenAPI schema pasted into the GPT builder.
What it contains
| Part | Meaning |
|---|---|
| servers | The web address of the service |
| paths | The things you can ask for (for example /orders) |
| methods | GET reads, POST sends, PUT or PATCH updates, DELETE removes |
| parameters | What you must send with a request |
| securitySchemes | How it checks who you are |
Why you care when migrating
OpenAI says Actions require an OpenAPI schema and do not transfer through plugin migration. Your schema is the best map of what to rebuild. The free checker lists endpoints, servers and authentication from a pasted schema. Whether another tool can import it directly: import support.
Next
Convert it to tool definitions and see webhooks for a simple replacement.
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
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