Add --force-model CLI alias for static routing

data/cli_flag_snapshot.txt

@@ -36,6 +36,7 @@
 --enable-pytest-compression
 --enable-pytest-full-suite-steering
 --force-context-window
+--force-model
 --force-set-project
 --gemini-api-base-url
 --gemini-api-key

data/test_suite_state.json

@@ -1,4 +1,4 @@
-{
-  "test_count": 3054,
-  "last_updated": "1760246496.86542"
+{
+  "test_count": 3017,
+  "last_updated": "1760308090.250383"
 }

src/core/cli.py

@@ -93,12 +93,19 @@ def build_cli_parser() -> argparse.ArgumentParser:
         choices=registered_backends,  # Dynamically populated
         help=argparse.SUPPRESS,
     )
-    parser.add_argument(
+    route_group = parser.add_mutually_exclusive_group()
+    route_group.add_argument(
         "--static-route",
         dest="static_route",
         metavar="BACKEND:MODEL",
         help="Force all requests to use this backend:model combination (e.g., gemini-cli-oauth-personal:gemini-2.5-pro)",
     )
+    route_group.add_argument(
+        "--force-model",
+        dest="force_model",
+        metavar="MODEL",
+        help="Force all requests to use this model while keeping the backend unchanged (alias for --static-route MODEL)",
+    )
 
     def validate_model_alias(value: str) -> tuple[str, str]:
         """Validate model alias format: pattern=replacement"""
@@ -647,6 +654,11 @@ def record_cli(path: str, value: Any, flag: str) -> None:
         backend_overrides["static_route"] = args.static_route
         os.environ["STATIC_ROUTE"] = args.static_route
         record_cli("backends.static_route", args.static_route, "--static-route")
+    elif getattr(args, "force_model", None) is not None:
+        backend_overrides = cli_overrides.setdefault("backends", {})
+        backend_overrides["static_route"] = args.force_model
+        os.environ["STATIC_ROUTE"] = args.force_model
+        record_cli("backends.static_route", args.force_model, "--force-model")
 
     # Model aliases configuration (CLI overrides config file)
     if getattr(args, "model_aliases", None) is not None:

tests/unit/test_cli.py

@@ -17,7 +17,7 @@ def clean_cli_environment():
     """Ensure clean environment for CLI tests to prevent contamination."""
     # Store original values
     original_env = {}
-    env_vars_to_clean = ["COMMAND_PREFIX", "MODEL_ALIASES"]
+    env_vars_to_clean = ["COMMAND_PREFIX", "MODEL_ALIASES", "STATIC_ROUTE"]
 
     for var in env_vars_to_clean:
         original_env[var] = os.environ.get(var)
@@ -223,6 +223,18 @@ def test_cli_context_window_override_environment_variable() -> None:
                 del os.environ["FORCE_CONTEXT_WINDOW"]
 
 
+def test_cli_force_model_argument_parsing() -> None:
+    """Test that the --force-model CLI argument forces static routing to the specified model."""
+
+    with patch("src.core.config.app_config.load_config", return_value=AppConfig()):
+        args = parse_cli_args(["--force-model", "gemini-2.5-pro"])
+        assert args.force_model == "gemini-2.5-pro"
+
+        config = _unwrap_config(apply_cli_args(args))
+        assert config.backends.static_route == "gemini-2.5-pro"
+        assert os.environ.get("STATIC_ROUTE") == "gemini-2.5-pro"
+
+
 def test_cli_pytest_compression_flags() -> None:
     """Test that --enable-pytest-compression and --disable-pytest-compression flags work."""
     # Patch load_config where it is looked up (in the 'cli' module)

tests/unit/test_static_route.py

@@ -7,6 +7,8 @@
 from src.core.domain.chat import ChatRequest
 from src.core.services.backend_service import BackendService
 
+from tests.unit.test_cli import _unwrap_config
+
 
 class TestStaticRoute:
     """Test suite for static_route override functionality."""
@@ -206,10 +208,12 @@ def test_cli_config_application(self):
             )
             assert config.backends.default_backend == "openai"
 
-    def test_cli_rejects_force_model(self):
-        """Test that --force-model is rejected (removed parameter)."""
-        from src.core.cli import parse_cli_args
+    def test_cli_accepts_force_model_alias(self):
+        """Test that --force-model is accepted as an alias for static routing."""
+        from src.core.cli import apply_cli_args, parse_cli_args
+
+        args = parse_cli_args(["--force-model", "gemini-2.5-pro"])
+        assert args.force_model == "gemini-2.5-pro"
 
-        # Should raise SystemExit because --force-model is not a valid argument
-        with pytest.raises(SystemExit):
-            parse_cli_args(["--force-model", "gemini-2.5-pro"])
+        config = _unwrap_config(apply_cli_args(args))
+        assert config.backends.static_route == "gemini-2.5-pro"