Generate MCP resources and templates on respective classes

src/fastmcp/resources/resource.py

@@ -1,8 +1,9 @@
 """Base classes and interfaces for FastMCP resources."""
 
 import abc
-from typing import Annotated
+from typing import Annotated, Any
 
+from mcp.types import Resource as MCPResource
 from pydantic import (
     AnyUrl,
     BaseModel,
@@ -38,6 +39,14 @@ class Resource(BaseModel, abc.ABC):
         pattern=r"^[a-zA-Z0-9]+/[a-zA-Z0-9\-+.]+$",
     )
 
+    @field_validator("mime_type", mode="before")
+    @classmethod
+    def set_default_mime_type(cls, mime_type: str | None) -> str:
+        """Set default MIME type if not provided."""
+        if mime_type:
+            return mime_type
+        return "text/plain"
+
     @field_validator("name", mode="before")
     @classmethod
     def set_default_name(cls, name: str | None, info: ValidationInfo) -> str:
@@ -57,3 +66,13 @@ class Resource(BaseModel, abc.ABC):
         if not isinstance(other, Resource):
             return False
         return self.model_dump() == other.model_dump()
+
+    def to_mcp_resource(self, **overrides: Any) -> MCPResource:
+        """Convert the resource to an MCPResource."""
+        kwargs = {
+            "uri": self.uri,
+            "name": self.name,
+            "description": self.description,
+            "mimeType": self.mime_type,
+        }
+        return MCPResource(**kwargs | overrides)

src/fastmcp/resources/resource_manager.py

@@ -7,8 +7,13 @@ from typing import Any
 from pydantic import AnyUrl
 
 from fastmcp.exceptions import ResourceError
-from fastmcp.resources import FunctionResource, Resource
-from fastmcp.resources.template import ResourceTemplate, match_uri_template
+from fastmcp.resources import FunctionResource
+from fastmcp.resources.resource import MCPResource, Resource
+from fastmcp.resources.template import (
+    MCPResourceTemplate,
+    ResourceTemplate,
+    match_uri_template,
+)
 from fastmcp.settings import DuplicateBehavior
 from fastmcp.utilities.logging import get_logger
 
@@ -227,6 +232,21 @@ class ResourceManager:
         logger.debug("Listing resources", extra={"count": len(self._resources)})
         return list(self._resources.values())
 
+    def list_mcp_resources(self) -> list[MCPResource]:
+        """List all registered resources in the format expected by the low-level MCP server."""
+
+        return [
+            resource.to_mcp_resource(uri=key)
+            for key, resource in self._resources.items()
+        ]
+
+    def list_mcp_resource_templates(self) -> list[MCPResourceTemplate]:
+        """List all registered resource templates in the format expected by the low-level MCP server."""
+        return [
+            template.to_mcp_template(uriTemplate=key)
+            for key, template in self._templates.items()
+        ]
+
     def get_templates(self) -> dict[str, ResourceTemplate]:
         """Get all registered templates, keyed by URI template."""
         return self._templates

src/fastmcp/resources/template.py

@@ -7,12 +7,14 @@ import re
 from collections.abc import Callable
 from typing import Annotated, Any
 
+from mcp.types import ResourceTemplate as MCPResourceTemplate
 from pydantic import (
     AnyUrl,
     BaseModel,
     BeforeValidator,
     Field,
     TypeAdapter,
+    field_validator,
     validate_call,
 )
 
@@ -62,6 +64,14 @@ class ResourceTemplate(BaseModel):
         description="JSON schema for function parameters"
     )
 
+    @field_validator("mime_type", mode="before")
+    @classmethod
+    def set_default_mime_type(cls, mime_type: str | None) -> str:
+        """Set default MIME type if not provided."""
+        if mime_type:
+            return mime_type
+        return "text/plain"
+
     @classmethod
     def from_function(
         cls,
@@ -144,3 +154,13 @@ class ResourceTemplate(BaseModel):
         if not isinstance(other, ResourceTemplate):
             return False
         return self.model_dump() == other.model_dump()
+
+    def to_mcp_template(self, **overrides: Any) -> MCPResourceTemplate:
+        """Convert the resource template to an MCPResourceTemplate."""
+        kwargs = {
+            "uriTemplate": self.uri_template,
+            "name": self.name,
+            "description": self.description,
+            "mimeType": self.mime_type,
+        }
+        return MCPResourceTemplate(**kwargs | overrides)

src/fastmcp/server/server.py

@@ -225,7 +225,12 @@ class FastMCP(Generic[LifespanResultT]):
         converted_result = _convert_to_content(result)
         return converted_result
 
+    def get_resources(self) -> dict[str, Resource]:
+        """Get all registered resources, indexed by registered key."""
+        return self._resource_manager.get_resources()
+
     def list_resources(self) -> list[Resource]:
+        """List all registered resources."""
         return self._resource_manager.list_resources()
 
     async def _mcp_list_resources(self) -> list[MCPResource]:
@@ -236,16 +241,7 @@ class FastMCP(Generic[LifespanResultT]):
         See `list_resources` for a more ergonomic way to list resources.
         """
 
-        resources = self.list_resources()
-        return [
-            MCPResource(
-                uri=resource.uri,
-                name=resource.name or "",
-                description=resource.description,
-                mimeType=resource.mime_type,
-            )
-            for resource in resources
-        ]
+        return self._resource_manager.list_mcp_resources()
 
     def list_resource_templates(self) -> list[ResourceTemplate]:
         return self._resource_manager.list_templates()
@@ -258,15 +254,7 @@ class FastMCP(Generic[LifespanResultT]):
         See `list_resource_templates` for a more ergonomic way to list resource
         templates.
         """
-        templates = self.list_resource_templates()
-        return [
-            MCPResourceTemplate(
-                uriTemplate=template.uri_template,
-                name=template.name,
-                description=template.description,
-            )
-            for template in templates
-        ]
+        return self._resource_manager.list_mcp_resource_templates()
 
     async def read_resource(self, uri: AnyUrl | str) -> str | bytes:
         """Read a resource by URI."""