Zapier has a dynamic way of loading things into a plugin, this may be a solution?
https://nla.zapier.com/api/v1/dynamic/docs
Otherwise, it is possible to build a plugin which is able to search a database of possible tasks and have the AI perform them via a dynamic API route (for example “/execute?task=calculate”).
The AI also doesn’t need the response to be exactly as defined in the openapi.json schema - it can understand it even when the response doesn’t follow the schema. The schema just helps to understand what the data means.