Add a warning that chip-device-ctrl is unmaintained. (#23724)
diff --git a/docs/guides/python_chip_controller_building.md b/docs/guides/python_chip_controller_building.md
index 7c1ac47..2d6ad82 100644
--- a/docs/guides/python_chip_controller_building.md
+++ b/docs/guides/python_chip_controller_building.md
@@ -1,3 +1,9 @@
+# Deprecation notice
+
+chip-device-ctrl is no longer maintained and should not be used.
+
+Matter-repl is the current python controller implementation.
+
# Working with Python CHIP Controller
The Python CHIP Controller is a tool that allows to commission a Matter device
