diff --git a/hermes_cli/auth.py b/hermes_cli/auth.py
index 3eadd5d70..37a971c3a 100644
--- a/hermes_cli/auth.py
+++ b/hermes_cli/auth.py
@@ -1541,8 +1541,20 @@ def detect_external_credentials() -> List[Dict[str, Any]]:
 # CLI Commands — login / logout
 # =============================================================================
 
-def _update_config_for_provider(provider_id: str, inference_base_url: str) -> Path:
-    """Update config.yaml and auth.json to reflect the active provider."""
+def _update_config_for_provider(
+    provider_id: str,
+    inference_base_url: str,
+    default_model: Optional[str] = None,
+) -> Path:
+    """Update config.yaml and auth.json to reflect the active provider.
+
+    When *default_model* is provided the function also writes it as the
+    ``model.default`` value.  This prevents a race condition where the
+    gateway (which re-reads config per-message) picks up the new provider
+    before the caller has finished model selection, resulting in a
+    mismatched model/provider (e.g. ``anthropic/claude-opus-4.6`` sent to
+    MiniMax's API).
+    """
     # Set active_provider in auth.json so auto-resolution picks this provider
     with _auth_store_lock():
         auth_store = _load_auth_store()
@@ -1576,6 +1588,15 @@ def _update_config_for_provider(provider_id: str, inference_base_url: str) -> Pa
     else:
         # Clear stale base_url to prevent contamination when switching providers
         model_cfg.pop("base_url", None)
+
+    # When switching to a non-OpenRouter provider, ensure model.default is
+    # valid for the new provider.  An OpenRouter-formatted name like
+    # "anthropic/claude-opus-4.6" will fail on direct-API providers.
+    if default_model:
+        cur_default = model_cfg.get("default", "")
+        if not cur_default or "/" in cur_default:
+            model_cfg["default"] = default_model
+
     config["model"] = model_cfg
 
     config_path.write_text(yaml.safe_dump(config, sort_keys=False))
diff --git a/hermes_cli/setup.py b/hermes_cli/setup.py
index 0b5a165cc..baff9e6ec 100644
--- a/hermes_cli/setup.py
+++ b/hermes_cli/setup.py
@@ -111,7 +111,17 @@ def _setup_provider_model_selection(config, provider_id, current_model, prompt_c
         custom = prompt_fn("Enter model name")
         if custom:
             _set_default_model(config, custom)
-    # else: keep current
+    else:
+        # "Keep current" selected — validate it's compatible with the new
+        # provider.  OpenRouter-formatted names (containing "/") won't work
+        # on direct-API providers and would silently break the gateway.
+        if "/" in (current_model or "") and provider_models:
+            print_warning(
+                f"Current model \"{current_model}\" looks like an OpenRouter model "
+                f"and won't work with {pconfig.name}. "
+                f"Switching to {provider_models[0]}."
+            )
+            _set_default_model(config, provider_models[0])
 
 
 def _sync_model_from_disk(config: Dict[str, Any]) -> None:
@@ -967,7 +977,7 @@ def setup_model_provider(config: dict):
         if existing_custom:
             save_env_value("OPENAI_BASE_URL", "")
             save_env_value("OPENAI_API_KEY", "")
-        _update_config_for_provider("zai", zai_base_url)
+        _update_config_for_provider("zai", zai_base_url, default_model="glm-5")
         _set_model_provider(config, "zai", zai_base_url)
 
     elif provider_idx == 5:  # Kimi / Moonshot
@@ -1000,7 +1010,7 @@ def setup_model_provider(config: dict):
         if existing_custom:
             save_env_value("OPENAI_BASE_URL", "")
             save_env_value("OPENAI_API_KEY", "")
-        _update_config_for_provider("kimi-coding", pconfig.inference_base_url)
+        _update_config_for_provider("kimi-coding", pconfig.inference_base_url, default_model="kimi-k2.5")
         _set_model_provider(config, "kimi-coding", pconfig.inference_base_url)
 
     elif provider_idx == 6:  # MiniMax
@@ -1033,7 +1043,7 @@ def setup_model_provider(config: dict):
         if existing_custom:
             save_env_value("OPENAI_BASE_URL", "")
             save_env_value("OPENAI_API_KEY", "")
-        _update_config_for_provider("minimax", pconfig.inference_base_url)
+        _update_config_for_provider("minimax", pconfig.inference_base_url, default_model="MiniMax-M2.5")
         _set_model_provider(config, "minimax", pconfig.inference_base_url)
 
     elif provider_idx == 7:  # MiniMax China
@@ -1066,7 +1076,7 @@ def setup_model_provider(config: dict):
         if existing_custom:
             save_env_value("OPENAI_BASE_URL", "")
             save_env_value("OPENAI_API_KEY", "")
-        _update_config_for_provider("minimax-cn", pconfig.inference_base_url)
+        _update_config_for_provider("minimax-cn", pconfig.inference_base_url, default_model="MiniMax-M2.5")
         _set_model_provider(config, "minimax-cn", pconfig.inference_base_url)
 
     elif provider_idx == 8:  # Anthropic
@@ -1170,7 +1180,7 @@ def setup_model_provider(config: dict):
             save_env_value("OPENAI_API_KEY", "")
         # Don't save base_url for Anthropic — resolve_runtime_provider()
         # always hardcodes it. Stale base_urls contaminate other providers.
-        _update_config_for_provider("anthropic", "")
+        _update_config_for_provider("anthropic", "", default_model="claude-opus-4-6")
         _set_model_provider(config, "anthropic")
 
     # else: provider_idx == 9 (Keep current) — only shown when a provider already exists