feat(registry): reject image-only models in chat model saves

EvoScientist/model_registry/errors.py

@@ -52,6 +52,7 @@ CAPABILITY_UNSUPPORTED_BY_ADAPTER = "CAPABILITY_UNSUPPORTED_BY_ADAPTER"
 MODEL_CAPABILITY_UNAVAILABLE = "MODEL_CAPABILITY_UNAVAILABLE"
 UNSUPPORTED_RUNTIME_PARAMETER = "UNSUPPORTED_RUNTIME_PARAMETER"
 MODEL_LIMITS_UNCONFIRMED = "MODEL_LIMITS_UNCONFIRMED"
+IMAGE_MODEL_NOT_CHAT_MODEL = "IMAGE_MODEL_NOT_CHAT_MODEL"
 CONTEXT_BUDGET_UNSATISFIABLE = "CONTEXT_BUDGET_UNSATISFIABLE"
 PROVIDER_UNREACHABLE = "PROVIDER_UNREACHABLE"
 
@@ -88,6 +89,7 @@ ERROR_HTTP_STATUS: dict[str, int] = {
     MODEL_CAPABILITY_UNAVAILABLE: 422,
     UNSUPPORTED_RUNTIME_PARAMETER: 422,
     MODEL_LIMITS_UNCONFIRMED: 422,
+    IMAGE_MODEL_NOT_CHAT_MODEL: 422,
     CONTEXT_BUDGET_UNSATISFIABLE: 422,
     PROVIDER_UNREACHABLE: 422,
     VALIDATION_FAILED: 422,

EvoScientist/model_registry/http_api.py

@@ -51,6 +51,7 @@ from .endpoint_policy import EndpointPolicy
 from .errors import (
     CREDENTIAL_NOT_CONFIGURED,
     FORBIDDEN,
+    IMAGE_MODEL_NOT_CHAT_MODEL,
     INVALID_REQUEST,
     MODEL_LIMITS_UNCONFIRMED,
     MODEL_NOT_AVAILABLE,
@@ -381,6 +382,26 @@ def validate_registry_save(
     ``resolve_parameters``, and the resolve-time tightening rules are
     enforced by the resolver/adapter layer.
     """
+    from EvoScientist.image_gen import is_image_generation_model
+
+    for provider_index, provider in enumerate(registry.providers):
+        for model_index, model in enumerate(provider.models):
+            if model.enabled and is_image_generation_model(model.upstream_model_id):
+                raise ModelRegistryError(
+                    IMAGE_MODEL_NOT_CHAT_MODEL,
+                    "Image-only models must be configured in the "
+                    "image_generation section of config.yaml, not as chat models.",
+                    details=[
+                        {
+                            "path": (
+                                f"providers[{provider_index}].models"
+                                f"[{model_index}].upstream_model_id"
+                            ),
+                            "code": IMAGE_MODEL_NOT_CHAT_MODEL,
+                        }
+                    ],
+                )
+
     for provider_index, provider in enumerate(registry.providers):
         provider_path = f"providers[{provider_index}]"
         try:

tests/test_model_registry_http.py

@@ -384,6 +384,17 @@ def test_put_registry_rejects_ssrf_endpoint(active_client):
     assert body["details"][0]["path"].startswith("providers[0].base_url")
 
 
+def test_put_registry_rejects_image_only_model(active_client):
+    registry = _current_registry(active_client)["registry"]
+    registry["providers"][0]["models"][0]["upstream_model_id"] = "gpt-image-2"
+
+    response = _put(active_client, registry)
+    assert response.status_code == 422
+    body = response.json()
+    assert body["code"] == "IMAGE_MODEL_NOT_CHAT_MODEL"
+    assert body["details"][0]["path"].endswith("upstream_model_id")
+
+
 def test_put_registry_rejects_unsupported_parameter(active_client):
     registry = _current_registry(active_client)["registry"]
     # The glm-5.2 contract caps temperature at 1.