Yes, you've got the overall process correct. Here's a step-by-step breakdown of what happens:

1. Client Fetches Edge Function: The client makes a fetch request to the Edge Function.

2. Edge Function Fetches Serverless Function: The Edge Function, in turn, makes a request to the Serverless Function.

3. Serverless Function Responds: The Serverless Function starts streaming data (using Server-Sent Events format) and responds with a status code of 200. This response, along with the headers and the stream as the body, gets returned to the Edge Function.

4. Edge Function Returns to Client: The Edge Function forwards the response from the Serverless Function to the client.

5. Client Reads the Stream: The client checks response.ok to ensure it's true (indicating a successful response) and then starts reading the stream. The client continues to receive data as it is streamed from the server.

6. Closing the Stream: Once the Serverless Function has finished streaming data, it calls closeResponseStream() to close the stream. This signals to the client that the stream has ended, and the client will stop reading the stream.

It's important to note that the data is streamed incrementally from the Serverless Function to the client, so the client can start processing the data before the stream is fully closed. This is one of the key advantages of using Server-Sent Events for streaming data.