update

Author: LadyBluenotes

src/routes/reference/rendering/render-to-stream.mdx

@@ -84,12 +84,12 @@ Callback invoked when a rendering error is encountered.
 
 - **Type:** `{ pipe: ..., pipeTo: ... }`
 
-Streaming controller with `pipe` and `pipeTo` methods.
+Streaming controller with `pipe` and `pipeTo` methods. The runtime implementation is also thenable and can resolve to the complete HTML string.
 
 ## Behavior
 
-- `renderToStream` writes the shell synchronously, including suspense fallback content.
-- Async content and serialized data continue streaming as resources resolve.
+- `renderToStream` is a server rendering API and is unsupported in browser bundles. It buffers the shell HTML, including suspense fallback content, and can flush it before later async fragments and serialized data stream as resources resolve.
+- `onCompleteShell` and `onCompleteAll` receive a `write()` helper for injecting additional output into the stream.
 - `pipe` writes to Node-style writable targets.
 - `pipeTo` writes to a `WritableStream`.