fix(spend): return 400 from /spend/calculate for a model with no pricing row (#42497)

* fix(spend): return 400 from /spend/calculate for a model with no pricing row

Co-Authored-By: Devin AI <158243242+devin-ai-integration[bot]@users.noreply.github.com>

* test(spend): assert error type and param for unpriced /spend/calculate

Co-Authored-By: Devin AI <158243242+devin-ai-integration[bot]@users.noreply.github.com>

* test(spend): move the repro to tests/integration

Co-Authored-By: Devin AI <158243242+devin-ai-integration[bot]@users.noreply.github.com>

* fix: alias ModelNotMappedError re-export to satisfy F401

Co-Authored-By: Devin AI <158243242+devin-ai-integration[bot]@users.noreply.github.com>

* fix(utils): raise ModelNotMappedError only when the pricing row is missing

Co-Authored-By: Devin AI <158243242+devin-ai-integration[bot]@users.noreply.github.com>

---------

Co-authored-by: kerry <kerry@berri.ai>
Co-authored-by: Devin AI <158243242+devin-ai-integration[bot]@users.noreply.github.com>

litellm/__init__.py

@@ -1402,6 +1402,7 @@ from .exceptions import (
     JSONSchemaValidationError,
     LITELLM_EXCEPTION_TYPES,
     MockException,
+    ModelNotMappedError as ModelNotMappedError,
 )
 from .budget_manager import BudgetManager
 from .proxy.proxy_cli import run_server

litellm/exceptions.py

@@ -991,6 +991,10 @@ LITELLM_EXCEPTION_TYPES: Final = [
 ]
 
 
+class ModelNotMappedError(Exception):
+    pass
+
+
 class BudgetExceededError(Exception):
     def __init__(
         self,

litellm/proxy/spend_tracking/spend_management_endpoints.py

@@ -2323,6 +2323,13 @@ async def calculate_spend(request: SpendCalculateRequest):
                 param=getattr(e, "param", "None"),
                 code=getattr(e, "status_code", status.HTTP_400_BAD_REQUEST),
             )
+        if isinstance(e, litellm.exceptions.ModelNotMappedError):
+            raise ProxyException(
+                message=str(e),
+                type="invalid_request_error",
+                param="model",
+                code=status.HTTP_400_BAD_REQUEST,
+            )
         error_msg: Final = f"{e}"
         raise ProxyException(
             message=getattr(e, "message", error_msg),

litellm/utils.py

@@ -472,6 +472,7 @@ from .exceptions import (
     BudgetExceededError,
     ContentPolicyViolationError,
     ContextWindowExceededError,
+    ModelNotMappedError,
     NotFoundError,
     OpenAIError,
     PermissionDeniedError,
@@ -5830,6 +5831,13 @@ def _is_potential_model_name_in_model_cost(
 _ABOVE_THRESHOLD_COST_KEY: Final = ABOVE_THRESHOLD_COST_KEY_PATTERN
 
 
+def _model_not_mapped_message(model: str, custom_llm_provider: str | None) -> str:
+    return (
+        f"This model isn't mapped yet. model={model}, custom_llm_provider={custom_llm_provider}. "
+        "Add it here - https://github.com/BerriAI/litellm/blob/main/model_prices_and_context_window.json."
+    )
+
+
 def _get_model_info_helper(
     model: str,
     custom_llm_provider: str | None = None,
@@ -6012,9 +6020,7 @@ def _get_model_info_helper(
                     key, _model_info = generalization
 
             if _model_info is None or key is None:
-                raise ValueError(
-                    "This model isn't mapped yet. Add it here - https://github.com/BerriAI/litellm/blob/main/model_prices_and_context_window.json"
-                )
+                raise ModelNotMappedError(_model_not_mapped_message(model, custom_llm_provider))
             _input_cost_per_token: float | None = _model_info.get("input_cost_per_token")
             if _input_cost_per_token is None:
                 # default value to 0, be noisy about this
@@ -6249,11 +6255,11 @@ def _get_model_info_helper(
                 if cost_key not in returned_model_info and _ABOVE_THRESHOLD_COST_KEY.search(cost_key) is not None:
                     returned_model_info[cost_key] = cost_value
             return returned_model_info
+    except ModelNotMappedError:
+        raise
     except Exception as e:
         verbose_logger.debug("Error getting model info: %s", e)
-        raise Exception(
-            f"This model isn't mapped yet. model={model}, custom_llm_provider={custom_llm_provider}. Add it here - https://github.com/BerriAI/litellm/blob/main/model_prices_and_context_window.json."
-        )
+        raise Exception(_model_not_mapped_message(model, custom_llm_provider))
 
 
 def _build_model_info(

tests/integration/contracts.json

@@ -275,6 +275,9 @@
     "tests/integration/spend/test_filtered_ledger.py::test_rotated_keys_users_and_model_groups_preserve_success_failure_cache_ledger": [
       "quota_management.spend_tracking.filtered_ledger_preserves_owner_identity_and_totals"
     ],
+    "tests/integration/spend/test_spend_calculate.py::test_spend_calculate_rejects_unpriced_model_with_400": [
+      "quota_management.spend_tracking.spend_calculate.rejects_unpriced_model"
+    ],
     "tests/integration/management/test_partial_update_sequences.py::test_restricted_actor_cannot_detach_key_from_project": [
       "mgmt.key.update.project_detach_denied_to_restricted_actor"
     ],

tests/integration/spend/test_spend_calculate.py

@@ -0,0 +1,20 @@
+import uuid
+from typing import Final
+
+import pytest
+from integration._support.client import JSON_OBJECT, Gateway, object_value, string_value
+
+
+@pytest.mark.covers("quota_management.spend_tracking.spend_calculate.rejects_unpriced_model")
+def test_spend_calculate_rejects_unpriced_model_with_400(gateway: Gateway) -> None:
+    model: Final = f"openrouter/integration-unpriced-{uuid.uuid4().hex}"
+    response: Final = gateway.request(
+        "POST",
+        "/spend/calculate",
+        {"model": model, "messages": [{"role": "user", "content": "price this request"}]},
+    )
+    assert response.status_code == 400, response.text
+    error: Final = object_value(JSON_OBJECT.validate_json(response.text)["error"])
+    assert error["type"] == "invalid_request_error", response.text
+    assert error["param"] == "model", response.text
+    assert model in string_value(error["message"]), response.text

tests/test_litellm/proxy/spend_tracking/test_spend_management_endpoints.py

@@ -257,6 +257,8 @@ from litellm.constants import LITTELM_INTERNAL_HEALTH_SERVICE_ACCOUNT_NAME
 from litellm.proxy._types import (
     LitellmUserRoles,
     Member,
+    ProxyException,
+    SpendCalculateRequest,
     SpendLogsPayload,
     UserAPIKeyAuth,
 )
@@ -7835,3 +7837,18 @@ def test_ui_view_request_response_internal_user_missing_row_forbidden(client, mo
         assert custom_logger.requested_ids == []
     finally:
         app.dependency_overrides.pop(ps.user_api_key_auth, None)
+
+
+@pytest.mark.asyncio
+async def test_calculate_spend_unpriced_model_returns_400():
+    model = "openrouter/unit-test-unpriced-model"
+    with patch("litellm.proxy.proxy_server.llm_router", None):
+        with pytest.raises(ProxyException) as exc_info:
+            await spend_management_endpoints.calculate_spend(
+                SpendCalculateRequest(model=model, messages=[{"role": "user", "content": "hi"}])
+            )
+
+    assert exc_info.value.code == "400"
+    assert exc_info.value.type == "invalid_request_error"
+    assert exc_info.value.param == "model"
+    assert model in exc_info.value.message

tests/test_litellm/test_utils.py

@@ -230,6 +230,13 @@ def test_get_model_info_prefers_exact_dated_key_over_stripped(
     assert info["key"] == expected_key
 
 
+def test_get_model_info_internal_failure_is_not_reported_as_unmapped() -> None:
+    with patch("litellm.utils._get_potential_model_names", side_effect=RuntimeError("malformed metadata")):
+        with pytest.raises(Exception, match="This model isn't mapped yet") as exc_info:
+            litellm.utils._get_model_info_helper(model="gpt-4o", custom_llm_provider="openai")
+    assert not isinstance(exc_info.value, litellm.ModelNotMappedError)
+
+
 def test_check_provider_match_azure_ai_allows_openai_and_azure():
     """
     Test that azure_ai provider can match openai and azure models.