diff --git a/pyproject.toml b/pyproject.toml
index 3e620c09..bcbf465e 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -11,7 +11,7 @@ license = { text = "MIT License" }
 readme = "README.md"
 
 dependencies = [
-    "lxml>=4.9.3,<6.0.0",
+    "lxml>=4.9.3,<7.0.0",
     "openai>=1.11.0,<3.0.0",
     "rich>=13.6.0,<15.0.0",
     "PettingZoo==1.25.0",