diff --git a/src/camera.rs b/src/camera.rs
index 95252c6..a10ae20 100644
--- a/src/camera.rs
+++ b/src/camera.rs
@@ -22,6 +22,11 @@
 //! crate does not speak, so those printers get no stream here and say so
 //! rather than advertising one that will not play.
 //!
+//! That is not just an inference from the missing field - it is confirmed at
+//! the network layer (2026-10-15). The H2C accepts TCP on 322; the P1P
+//! *refuses* 322 and listens on 6000. So a P1P has no RTSP endpoint to
+//! restream, and no amount of guessing a URL would produce one.
+//!
 //! That is also why this module reads the *reported* URL and never builds one
 //! from the printer's IP: the fact that a printer has a camera and the fact
 //! that the camera has an RTSP endpoint are different facts, and only the