refactor: clean up fresh tech debt from 2026-09-28 (#43674)

* refactor: clean up fresh tech debt from 2026-09-28

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

* refactor: group leaderboard rows in one pass and wrap docstring at 120

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

---------

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

litellm/proxy/_experimental/mcp_server/tool_catalog_guard.py

@@ -39,10 +39,10 @@ class _ScanKwargs(TypedDict):
     server_name: ReadOnly[str]
     mcp_rate_limit_server_name: ReadOnly[str]
     user_api_key_auth: ReadOnly[UserAPIKeyAuth | None]
-    user_api_key_user_id: ReadOnly[object]
-    user_api_key_team_id: ReadOnly[object]
-    user_api_key_end_user_id: ReadOnly[object]
-    user_api_key_hash: ReadOnly[object]
+    user_api_key_user_id: ReadOnly[str | None]
+    user_api_key_team_id: ReadOnly[str | None]
+    user_api_key_end_user_id: ReadOnly[str | None]
+    user_api_key_hash: ReadOnly[str | None]
     headers: ReadOnly[Mapping[str, str]]
     mcp_tool_description: ReadOnly[str]
     mcp_input_schema: ReadOnly[Mapping[str, object]]
@@ -208,10 +208,10 @@ async def _guarded_catalog_entry(
         "server_name": server.name,
         "mcp_rate_limit_server_name": server.alias or server.server_name or server.name,
         "user_api_key_auth": user_api_key_auth,
-        "user_api_key_user_id": getattr(user_api_key_auth, "user_id", None),
-        "user_api_key_team_id": getattr(user_api_key_auth, "team_id", None),
-        "user_api_key_end_user_id": getattr(user_api_key_auth, "end_user_id", None),
-        "user_api_key_hash": getattr(user_api_key_auth, "api_key", None),
+        "user_api_key_user_id": user_api_key_auth.user_id if user_api_key_auth else None,
+        "user_api_key_team_id": user_api_key_auth.team_id if user_api_key_auth else None,
+        "user_api_key_end_user_id": user_api_key_auth.end_user_id if user_api_key_auth else None,
+        "user_api_key_hash": user_api_key_auth.api_key if user_api_key_auth else None,
         "headers": logging_safe_mcp_headers(raw_headers),
         "mcp_tool_description": tool.description or "",
         "mcp_input_schema": tool.input_schema,

litellm/proxy/auth/auth_checks.py

@@ -591,10 +591,9 @@ def _is_cost_explicitly_configured(model: str, llm_router: "Router") -> bool:
 
     The group is resolved through ``Router.get_model_list()``, the same resolution
     ``get_model_group_info()`` applies when the caller reads the cost a few lines earlier, so the
-    two lookups cannot disagree: names defined in ``Router.model_group_alias`` are not
-    ``model_name`` entries in ``Router.model_list``, and scanning that list by exact name reported
-    every aliased group as unconfigured. It also reaches a deployment that prices itself through
-    its ``model_info`` block, whose entry lands in the cost map under the deployment id.
+    two lookups cannot disagree, including for names defined in ``Router.model_group_alias``.
+    It also reaches a deployment that prices itself through its ``model_info`` block, whose entry
+    lands in the cost map under the deployment id.
     """
     for deployment in llm_router.get_model_list(model_name=model) or ():
         model_id = (deployment.get("model_info") or _EMPTY_COST_ENTRY).get("id")

litellm/proxy/db/model_usage_rollup.py

@@ -22,12 +22,16 @@ def model_usage_task_type(request_tags: str) -> str:
         tags: Final = _TAGS.validate_json(request_tags)
     except ValidationError:
         return MODEL_INSIGHTS_DEFAULT_TASK
-    for tag in tags:
-        if isinstance(tag, str) and tag.startswith(MODEL_INSIGHTS_TASK_TAG_PREFIX):
-            task = tag.removeprefix(MODEL_INSIGHTS_TASK_TAG_PREFIX)
-            if task in load_model_insight_tasks():
-                return task
-    return MODEL_INSIGHTS_DEFAULT_TASK
+    return next(
+        (
+            task
+            for tag in tags
+            if isinstance(tag, str)
+            and tag.startswith(MODEL_INSIGHTS_TASK_TAG_PREFIX)
+            and (task := tag.removeprefix(MODEL_INSIGHTS_TASK_TAG_PREFIX)) in load_model_insight_tasks()
+        ),
+        MODEL_INSIGHTS_DEFAULT_TASK,
+    )
 
 
 def _is_internal_call(metadata: str) -> bool:

litellm/proxy/management_endpoints/model_insights_endpoints.py

@@ -1,3 +1,5 @@
+import functools
+import itertools
 from collections.abc import Mapping
 from datetime import date, datetime, timedelta, timezone
 from typing import Annotated, Final
@@ -111,14 +113,20 @@ def _daily_metric(row: _GroupedDaily) -> ModelInsightDailyMetric:
 
 def _summarize_tasks(rows: list[_GroupedTask], metric: ModelInsightsMetric) -> list[ModelInsightTaskSummary]:
     catalog: Final = load_model_insight_tasks()
-    totals: Final[dict[str, float]] = {}
-    leaders: Final[dict[str, _GroupedTask]] = {}
-    for row in rows:
-        value = _rank_value(row, metric)
-        totals[row.task_type] = totals.get(row.task_type, 0.0) + value
-        leader = leaders.get(row.task_type)
-        if leader is None or value > _rank_value(leader, metric):
-            leaders[row.task_type] = row
+    first_seen: Final = {task: index for index, task in enumerate(dict.fromkeys(row.task_type for row in rows))}
+    by_task: Final = {
+        task: tuple(group)
+        for task, group in itertools.groupby(
+            sorted(rows, key=lambda row: first_seen[row.task_type]), key=lambda row: row.task_type
+        )
+    }
+    totals: Final = {
+        task: functools.reduce(lambda total, row: total + _rank_value(row, metric), task_rows, 0.0)
+        for task, task_rows in by_task.items()
+    }
+    leaders: Final = {
+        task: max(task_rows, key=lambda row: _rank_value(row, metric)) for task, task_rows in by_task.items()
+    }
     grand: Final = sum(totals.values())
     return [
         ModelInsightTaskSummary(

litellm/rust_bridge/callbacks_legacy_python.py

@@ -16,6 +16,7 @@ from dataclasses import dataclass
 from typing import (
     TYPE_CHECKING,
     Final,
+    Literal,
     Protocol,
     cast,  # noqa: TID251  # bounded compatibility calls into legacy Python integrations
 )
@@ -231,6 +232,10 @@ def defer_success(logger: LoggingSurface, pending: object) -> None:
     setattr(logger, "_native_pending_logging", pending)
 
 
+def _cache_hit(logger: LoggingSurface) -> Literal[True] | None:
+    return True if logger.model_call_details.get("cache_hit") is True else None
+
+
 def sync_success_for_async_call(
     logger: LoggingSurface, response: object, start: datetime.datetime, end: datetime.datetime
 ) -> None:
@@ -238,7 +243,7 @@ def sync_success_for_async_call(
         result=response,
         start_time=start,
         end_time=end,
-        cache_hit=True if logger.model_call_details.get("cache_hit") is True else None,
+        cache_hit=_cache_hit(logger),
     )
 
 
@@ -265,16 +270,14 @@ def submit_success(logger: LoggingSurface, response: object, start: datetime.dat
         response,
         start,
         end,
-        cache_hit=True if logger.model_call_details.get("cache_hit") is True else None,
+        cache_hit=_cache_hit(logger),
     )
 
 
 def async_success_handler(
     logger: LoggingSurface, response: object, start: datetime.datetime, end: datetime.datetime
 ) -> Coroutine[object, object, None]:
-    return logger.async_success_handler(
-        response, start, end, cache_hit=True if logger.model_call_details.get("cache_hit") is True else None
-    )
+    return logger.async_success_handler(response, start, end, cache_hit=_cache_hit(logger))
 
 
 def enqueue_logging(coroutine: Coroutine[object, object, None]) -> None:

tests/test_litellm/proxy/management_endpoints/test_model_insights_endpoints.py

@@ -122,7 +122,7 @@ def test_model_insights_scopes_daily_to_ranked_deployments() -> None:
 def _task_rows() -> list[dict[str, object]]:
     def row(task: str, group: str, requests: str, spend: float) -> dict[str, object]:
         base = _grouped_row(task_type=task, model_group=group, model=group, custom_llm_provider="openai")
-        base["_sum"].update({"request_count": requests, "spend": spend})  # type: ignore[union-attr]
+        base["_sum"].update({"request_count": requests, "spend": spend})
         return base
 
     return [