diff --git a/backend/apps/subscription/free_trial.py b/backend/apps/subscription/free_trial.py
index 8ae35069..91047875 100644
--- a/backend/apps/subscription/free_trial.py
+++ b/backend/apps/subscription/free_trial.py
@@ -177,6 +177,12 @@ async def arm_free_trial(settings_obj) -> dict:
         settings_obj.connection_mode = "free-trial"
         settings_obj.free_trial_token = data.get("trial_token")
         settings_obj.openswarm_proxy_url = base
+        # The free lane only routes Claude-family ids (dispatch needs api_type=anthropic).
+        # A leftover non-Claude pick (e.g. gemini) would skip the proxy and fail, so snap
+        # to Haiku, which is the tier the cloud serves the free run as anyway.
+        cur = getattr(settings_obj, "default_model", "") or ""
+        if not cur.startswith(("sonnet", "haiku", "opus")):
+            settings_obj.default_model = "haiku"
         await save_settings_async(settings_obj)
         await _sync_routing(settings_obj)
         return {"armed": True, "runs_remaining": remaining, "runs_limit": settings_obj.free_trial_runs_limit}