diff --git a/capnp-rpc/examples/streaming/README.md b/capnp-rpc/examples/streaming/README.md
index b7f7f5384..17942b1fd 100644
--- a/capnp-rpc/examples/streaming/README.md
+++ b/capnp-rpc/examples/streaming/README.md
@@ -11,3 +11,8 @@ Then start any number of clients like this:
 ```
 cargo run client 127.0.0.1:5000 1000000 64000
 ```
+
+The `1000000` argument above means the message
+stream will have a total of 1000000 bytes.
+The `64000` argument means that the flow control window
+will be set to 64000 bytes.