Their API docs for embeddings also don't talk about using them to get outside of the context size limit; instead, the way I've used it and seen others is "create embeddings from documents to enable fast search for relevant documents to populate in context" which still requires a separate data store.
https://platform.openai.com/docs/guides/chat - this API endpoint for completions doesn't take embeddings, just messages.
Their API docs for embeddings also don't talk about using them to get outside of the context size limit; instead, the way I've used it and seen others is "create embeddings from documents to enable fast search for relevant documents to populate in context" which still requires a separate data store.