diff --git a/src/core/registry.py b/src/core/registry.py
index 99ade3c..321903d 100644
--- a/src/core/registry.py
+++ b/src/core/registry.py
@@ -20,4 +20,5 @@ def build_env(env_name: str, cfg: DictConfig) -> BaseEnv:
 
     env_cls, config_cls = ENV_REGISTRY[env_name]
     env_dict = OmegaConf.to_container(cfg.env, resolve=True)
+    env_dict.pop("hpo", None)  # HPO range metadata — not an env config field
     return env_cls(config_cls(**env_dict))