fix: change Resource URI fields from AnyUrl to str (#1863)

src/mcp/types.py

@@ -5,7 +5,6 @@ from datetime import datetime
 from typing import Annotated, Any, Final, Generic, Literal, TypeAlias, TypeVar
 
 from pydantic import BaseModel, ConfigDict, Field, FileUrl, RootModel
-from pydantic.networks import AnyUrl, UrlConstraints
 
 LATEST_PROTOCOL_VERSION = "2025-11-25"
 
@@ -756,7 +755,7 @@ class Annotations(BaseModel):
 class Resource(BaseMetadata):
     """A known resource that the server is capable of reading."""
 
-    uri: Annotated[AnyUrl, UrlConstraints(host_required=False)]
+    uri: str
     """The URI of this resource."""
     description: str | None = None
     """A description of what this resource represents."""
@@ -827,7 +826,7 @@ class ListResourceTemplatesResult(PaginatedResult):
 class ReadResourceRequestParams(RequestParams):
     """Parameters for reading a resource."""
 
-    uri: Annotated[AnyUrl, UrlConstraints(host_required=False)]
+    uri: str
     """
     The URI of the resource to read. The URI can use any protocol; it is up to the
     server how to interpret it.
@@ -845,7 +844,7 @@ class ReadResourceRequest(Request[ReadResourceRequestParams, Literal["resources/
 class ResourceContents(BaseModel):
     """The contents of a specific resource or sub-resource."""
 
-    uri: Annotated[AnyUrl, UrlConstraints(host_required=False)]
+    uri: str
     """The URI of this resource."""
     mimeType: str | None = None
     """The MIME type of this resource, if known."""
@@ -895,7 +894,7 @@ class ResourceListChangedNotification(
 class SubscribeRequestParams(RequestParams):
     """Parameters for subscribing to a resource."""
 
-    uri: Annotated[AnyUrl, UrlConstraints(host_required=False)]
+    uri: str
     """
     The URI of the resource to subscribe to. The URI can use any protocol; it is up to
     the server how to interpret it.
@@ -916,7 +915,7 @@ class SubscribeRequest(Request[SubscribeRequestParams, Literal["resources/subscr
 class UnsubscribeRequestParams(RequestParams):
     """Parameters for unsubscribing from a resource."""
 
-    uri: Annotated[AnyUrl, UrlConstraints(host_required=False)]
+    uri: str
     """The URI of the resource to unsubscribe from."""
     model_config = ConfigDict(extra="allow")
 
@@ -934,7 +933,7 @@ class UnsubscribeRequest(Request[UnsubscribeRequestParams, Literal["resources/un
 class ResourceUpdatedNotificationParams(NotificationParams):
     """Parameters for resource update notifications."""
 
-    uri: Annotated[AnyUrl, UrlConstraints(host_required=False)]
+    uri: str
     """
     The URI of the resource that has been updated. This might be a sub-resource of the
     one that the client actually subscribed to.