diff --git a/hermes_cli/models.py b/hermes_cli/models.py
index 93a5111c56..10b63cbbb4 100644
--- a/hermes_cli/models.py
+++ b/hermes_cli/models.py
@@ -1452,7 +1452,8 @@ def detect_static_provider_for_model(
 ) -> Optional[tuple[str, str]]:
     """Auto-detect a provider from static catalogs only.
 
-    Returns ``(provider_id, model_name)`` — the model name may be remapped
+    Returns ``(provider_id, model_name)``. The model name may be remapped
+    when a static alias or bare provider name resolves to a catalog default.
     Returns ``None`` when no confident match is found.
     """
     name = (model_name or "").strip()
diff --git a/tests/test_tui_gateway_server.py b/tests/test_tui_gateway_server.py
index d4cdab8421..f7eacb6859 100644
--- a/tests/test_tui_gateway_server.py
+++ b/tests/test_tui_gateway_server.py
@@ -562,6 +562,8 @@ def test_config_set_model_syncs_tui_provider_env(monkeypatch):
 
         assert resp["result"]["value"] == "anthropic/claude-sonnet-4.6"
         assert os.environ["HERMES_TUI_PROVIDER"] == "anthropic"
+        assert os.environ["HERMES_MODEL"] == "anthropic/claude-sonnet-4.6"
+        assert os.environ["HERMES_INFERENCE_MODEL"] == "anthropic/claude-sonnet-4.6"
     finally:
         server._sessions.clear()
 
diff --git a/tui_gateway/server.py b/tui_gateway/server.py
index 7f981663a3..81a2a98e01 100644
--- a/tui_gateway/server.py
+++ b/tui_gateway/server.py
@@ -774,6 +774,7 @@ def _apply_model_switch(sid: str, session: dict, raw_input: str) -> dict:
         _emit("session.info", sid, _session_info(agent))
 
     os.environ["HERMES_MODEL"] = result.new_model
+    os.environ["HERMES_INFERENCE_MODEL"] = result.new_model
     # Keep the process-level provider env var in sync with the user's explicit
     # choice so any ambient re-resolution (credential pool refresh, compressor
     # rebuild, aux clients) resolves to the new provider instead of the