diff --git a/plugins/cortex-code/scripts/router/prompt_filter.py b/plugins/cortex-code/scripts/router/prompt_filter.py
index 0d0a3ef..a9e337d 100644
--- a/plugins/cortex-code/scripts/router/prompt_filter.py
+++ b/plugins/cortex-code/scripts/router/prompt_filter.py
@@ -5,6 +5,7 @@
 and if matched, prints a routing instruction to stdout that gets injected
 into the conversation context. Runs in <50ms -- no LLM calls, no network.
 """
+from __future__ import annotations
 
 import sys
 import re