diff --git a/docs/misc/hypfs-paths.pandoc b/docs/misc/hypfs-paths.pandoc
index a111c6f25c..81d70bb80c 100644
--- a/docs/misc/hypfs-paths.pandoc
+++ b/docs/misc/hypfs-paths.pandoc
@@ -5,6 +5,9 @@ in the Xen hypervisor file system (hypfs).
 
 The hypervisor file system can be accessed via the xenhypfs tool.
 
+The availability of the hypervisor file system depends on the hypervisor
+config option CONFIG_HYPFS, which is on per default.
+
 ## Notation
 
 The hypervisor file system is similar to the Linux kernel's sysfs.
@@ -64,6 +67,23 @@ the list elements separated by spaces, e.g. "dom0 PCID-on".
 The entry would be writable and it would exist on X86 only and only if the
 hypervisor is configured to support PV guests.
 
+# Stability
+
+Path *presence* is not stable, but path *meaning* is always stable: if a tool
+you write finds a path present, it can rely on behavior in future versions of
+the hypervisors, and in different configurations.  Specifically:
+
+1. Conditions under which paths are used may be extended, restricted, or
+   removed.  For example, a path that’s always available only on ARM systems
+   may become available on x86; or a path available on both systems may be
+   restricted to only appearing on ARM systems.  Paths may also disappear
+   entirely.
+2. However, the meaning of a path will never change.  If a path is present,
+   it will always have exactly the meaning that it always had.  In order to
+   maintain this, removed paths should be retained with the tag [REMOVED].
+   The path may be restored *only* if the restored version of the path is
+   compatible with the previous functionality.
+
 ## Example
 
 A populated Xen hypervisor file system might look like the following example: