Enable ruff for https://docs.astral.sh/ruff/rules/banned-api

Author: Kludex

pyproject.toml

@@ -125,15 +125,16 @@ extend-exclude = ["README.md"]
 
 [tool.ruff.lint]
 select = [
-    "C4",   # flake8-comprehensions
-    "C90",  # mccabe
-    "D212", # pydocstyle: multi-line docstring summary should start at the first line
-    "E",    # pycodestyle
-    "F",    # pyflakes
-    "I",    # isort
-    "PERF", # Perflint
-    "PL",   # Pylint
-    "UP",   # pyupgrade
+    "C4",     # flake8-comprehensions
+    "C90",    # mccabe
+    "D212",   # pydocstyle: multi-line docstring summary should start at the first line
+    "E",      # pycodestyle
+    "F",      # pyflakes
+    "I",      # isort
+    "PERF",   # Perflint
+    "PL",     # Pylint
+    "UP",     # pyupgrade
+    "TID251", # https://docs.astral.sh/ruff/rules/banned-api/
 ]
 ignore = ["PERF203", "PLC0415", "PLR0402"]
 

src/mcp/server/auth/handlers/authorize.py

@@ -2,7 +2,8 @@
 from dataclasses import dataclass
 from typing import Any, Literal
 
-from pydantic import AnyUrl, BaseModel, Field, RootModel, ValidationError
+# TODO(Marcelo): We should drop the `RootModel`.
+from pydantic import AnyUrl, BaseModel, Field, RootModel, ValidationError  # noqa: TID251
 from starlette.datastructures import FormData, QueryParams
 from starlette.requests import Request
 from starlette.responses import RedirectResponse, Response

src/mcp/server/fastmcp/utilities/func_metadata.py

@@ -6,7 +6,7 @@
 from typing import Annotated, Any, cast, get_args, get_origin, get_type_hints
 
 import pydantic_core
-from pydantic import BaseModel, ConfigDict, Field, RootModel, WithJsonSchema, create_model
+from pydantic import BaseModel, ConfigDict, Field, WithJsonSchema, create_model
 from pydantic.fields import FieldInfo
 from pydantic.json_schema import GenerateJsonSchema, JsonSchemaWarningKind
 from typing_extensions import is_typeddict
@@ -477,6 +477,8 @@ def _create_wrapped_model(func_name: str, annotation: Any) -> type[BaseModel]:
 
 def _create_dict_model(func_name: str, dict_annotation: Any) -> type[BaseModel]:
     """Create a RootModel for dict[str, T] types."""
+    # TODO(Marcelo): We should not rely on RootModel for this.
+    from pydantic import RootModel  # noqa: TID251
 
     class DictModel(RootModel[dict_annotation]):
         pass