Drop the removed-name hint machinery from mcp.types

The _REMOVED map and module __getattr__ intercepted the v1 names that
no longer exist to name their replacement in the error. That is extra
mechanism to maintain for a one-time migration nudge; a name that does
not exist should simply fail to import like any other. Remove it and its
tests, leaving mcp.types as a plain star mirror. The migration guide's
removed-names table still names each replacement.

Author: maxisbey

docs/migration.md

@@ -14,7 +14,7 @@ Every section heading below names the API it affects, so searching this page for
 |---|---|---|
 | `FastMCP` renamed to `MCPServer` | `ModuleNotFoundError: No module named 'mcp.server.fastmcp'` | [`FastMCP` renamed](#fastmcp-renamed-to-mcpserver) |
 | Fields renamed from camelCase to snake_case | `AttributeError: 'Tool' object has no attribute 'inputSchema'` | [snake_case fields](#field-names-changed-from-camelcase-to-snake_case) |
-| `mcp.types` names removed | `AttributeError: mcp.types.Content was removed in v2; use ContentBlock.` | [Removed types](#removed-type-aliases-and-classes) |
+| `mcp.types` names removed | `ImportError: cannot import name 'Content' from 'mcp.types'` | [Removed types](#removed-type-aliases-and-classes) |
 | `McpError` renamed to `MCPError` | `ImportError: cannot import name 'McpError' from 'mcp'` | [`McpError` renamed](#mcperror-renamed-to-mcperror) |
 | Resource URIs are `str`, not `AnyUrl` | `AttributeError: 'str' object has no attribute 'host'` | [URI type](#resource-uri-type-changed-from-anyurl-to-str) |
 | Message unions (`ServerNotification`, `JSONRPCMessage`, ...) are plain unions, not `RootModel` | `AttributeError: 'LoggingMessageNotification' object has no attribute 'root'` | [`RootModel` → unions](#replace-rootmodel-by-union-types-with-typeadapter-validation) |
@@ -216,11 +216,10 @@ SDK.** That is the point of the split: tooling and lightweight clients can depen
 protocol schema without pulling in `httpx2`, `starlette`, `uvicorn`, and the rest of the
 server/transport stack.
 
-Reading a name that no longer exists (listed under
-[Removed type aliases and classes](#removed-type-aliases-and-classes)) as
-`mcp.types.Content` raises an `AttributeError` that names its replacement; a
-`from mcp.types import Content` of one raises a plain `ImportError` (Python discards the hint on
-that path, but it still fails fast).
+Names that no longer exist (listed under
+[Removed type aliases and classes](#removed-type-aliases-and-classes)) fail on import or
+attribute access with an ordinary `ImportError` / `AttributeError`; the table below names each
+replacement.
 
 The supported import surface is the package plus its `jsonrpc`, `methods`, and `version`
 submodules, and each has both spellings: `mcp.types` / `mcp_types`, `mcp.types.jsonrpc` /

src/mcp/types/__init__.py

@@ -29,40 +29,3 @@
 from . import jsonrpc as jsonrpc
 from . import methods as methods
 from . import version as version
-
-# Names v1's mcp.types exposed that no longer exist. A bare "cannot import name"
-# leaves people grepping; naming the replacement finishes the migration step.
-_REMOVED = {
-    "Content": "use ContentBlock",
-    "ResourceReference": "use ResourceTemplateReference",
-    "Cursor": "use str",
-    "AnyFunction": "use Callable[..., Any]",
-    "MethodT": "it was an internal TypeVar, not public API",
-    "RequestParamsT": "it was an internal TypeVar, not public API",
-    "NotificationParamsT": "it was an internal TypeVar, not public API",
-    "ClientRequestType": "the union is now the bare name ClientRequest",
-    "ClientNotificationType": "the union is now the bare name ClientNotification",
-    "ClientResultType": "the union is now the bare name ClientResult",
-    "ServerRequestType": "the union is now the bare name ServerRequest",
-    "ServerNotificationType": "the union is now the bare name ServerNotification",
-    "ServerResultType": "the union is now the bare name ServerResult",
-    "TaskExecutionMode": "use the string literals directly",
-    "TASK_FORBIDDEN": "use the string literal 'forbidden'",
-    "TASK_OPTIONAL": "use the string literal 'optional'",
-    "TASK_REQUIRED": "use the string literal 'required'",
-    "TASK_STATUS_CANCELLED": "use the string literal 'cancelled'; TaskStatus remains",
-    "TASK_STATUS_COMPLETED": "use the string literal 'completed'; TaskStatus remains",
-    "TASK_STATUS_FAILED": "use the string literal 'failed'; TaskStatus remains",
-    "TASK_STATUS_INPUT_REQUIRED": "use the string literal 'input_required'; TaskStatus remains",
-    "TASK_STATUS_WORKING": "use the string literal 'working'; TaskStatus remains",
-}
-
-
-def __getattr__(name: str) -> object:
-    if (hint := _REMOVED.get(name)) is not None:
-        # AttributeError as PEP 562 requires, so hasattr() and getattr(..., default)
-        # still take their fallback path. The cost: `from mcp.types import Content`
-        # discards this message for CPython's generic "cannot import name" (still
-        # fail-fast); attribute access, the far more common v1 spelling, keeps it.
-        raise AttributeError(f"mcp.types.{name} was removed in v2; {hint}. See the migration guide.")
-    raise AttributeError(f"module {__name__!r} has no attribute {name!r}")

tests/test_types.py

@@ -485,35 +485,6 @@ def test_mcp_types_submodules_mirror_mcp_types_submodules_exactly(mirror: Module
     _assert_mirrors(mirror, source)
 
 
-def test_mcp_types_attribute_access_names_the_replacement_for_a_removed_name():
-    """SDK-defined: reading a v1 name that no longer exists names its v2 replacement."""
-    with pytest.raises(AttributeError) as exc_info:
-        getattr(mcp.types, "Content")
-    assert str(exc_info.value) == snapshot(
-        "mcp.types.Content was removed in v2; use ContentBlock. See the migration guide."
-    )
-    # AttributeError (not ImportError) keeps the introspection contract for probing code.
-    assert not hasattr(mcp.types, "Content")
-    assert getattr(mcp.types, "Content", None) is None
-
-
-def test_mcp_types_from_import_of_a_removed_name_still_fails_fast():
-    """SDK-defined: `from mcp.types import <removed>` raises rather than importing a stale name.
-
-    CPython builds this ImportError itself and discards the module's hint text, so only the
-    exception type is asserted; the hint is on the attribute-access path above.
-    """
-    with pytest.raises(ImportError):
-        exec("from mcp.types import Content")
-
-
-def test_mcp_types_unknown_attribute_raises_attribute_error():
-    """SDK-defined: an unknown attribute is a normal AttributeError, so `hasattr` returns False."""
-    with pytest.raises(AttributeError):
-        getattr(mcp.types, "not_a_protocol_type")
-    assert not hasattr(mcp.types, "not_a_protocol_type")
-
-
 def test_bare_import_mcp_binds_the_types_submodule():
     """SDK-defined: `import mcp` alone binds `mcp.types`, so v1's `mcp.types.Tool` idiom works.