Backport r82456.
diff --git a/Doc/library/dis.rst b/Doc/library/dis.rst
index 6871d7e..95edac9 100644
--- a/Doc/library/dis.rst
+++ b/Doc/library/dis.rst
@@ -6,11 +6,17 @@
    :synopsis: Disassembler for Python bytecode.
 
 
-The :mod:`dis` module supports the analysis of Python :term:`bytecode` by disassembling
-it.  Since there is no Python assembler, this module defines the Python assembly
-language.  The Python bytecode which this module takes as an input is defined
-in the file  :file:`Include/opcode.h` and used by the compiler and the
-interpreter.
+The :mod:`dis` module supports the analysis of CPython :term:`bytecode` by
+disassembling it. The CPython bytecode which this module takes as an
+input is defined in the file :file:`Include/opcode.h` and used by the compiler
+and the interpreter.
+
+.. impl-detail::
+
+   Bytecode is an implementation detail of the CPython interpreter!  No
+   guarantees are made that bytecode will not be added, removed, or changed
+   between versions of Python.  Use of this module should not be considered to
+   work across Python VMs or Python releases.
 
 Example: Given the function :func:`myfunc`::