Merge branch 'main' into modelcontextprotocol#552

Author: DanielAvdar

README.md

@@ -402,6 +402,9 @@ mcp = FastMCP("StatefulServer")
 # Stateless server (no session persistence)
 mcp = FastMCP("StatelessServer", stateless_http=True)
 
+# Stateless server (no session persistence, no sse stream with supported client)
+mcp = FastMCP("StatelessServer", stateless_http=True, json_response=True)
+
 # Run server with streamable_http transport
 mcp.run(transport="streamable-http")
 ```
@@ -434,15 +437,22 @@ def add_two(n: int) -> int:
 
 ```python
 # main.py
+import contextlib
 from fastapi import FastAPI
 from mcp.echo import echo
 from mcp.math import math
 
 
-app = FastAPI()
+# Create a combined lifespan to manage both session managers
+@contextlib.asynccontextmanager
+async def lifespan(app: FastAPI):
+    async with contextlib.AsyncExitStack() as stack:
+        await stack.enter_async_context(echo.mcp.session_manager.run())
+        await stack.enter_async_context(math.mcp.session_manager.run())
+        yield
+
 
-# Use the session manager's lifespan
-app = FastAPI(lifespan=lambda app: echo.mcp.session_manager.run())
+app = FastAPI(lifespan=lifespan)
 app.mount("/echo", echo.mcp.streamable_http_app())
 app.mount("/math", math.mcp.streamable_http_app())
 ```

examples/servers/simple-auth/mcp_simple_auth/__main__.py

@@ -4,4 +4,4 @@
 
 from mcp_simple_auth.server import main
 
-sys.exit(main())
+sys.exit(main())  # type: ignore[call-arg]

examples/servers/simple-prompt/mcp_simple_prompt/__main__.py

@@ -2,4 +2,4 @@
 
 from .server import main
 
-sys.exit(main())
+sys.exit(main())  # type: ignore[call-arg]

examples/servers/simple-resource/mcp_simple_resource/__main__.py

@@ -2,4 +2,4 @@
 
 from .server import main
 
-sys.exit(main())
+sys.exit(main())  # type: ignore[call-arg]

examples/servers/simple-resource/mcp_simple_resource/server.py

@@ -2,7 +2,7 @@
 import click
 import mcp.types as types
 from mcp.server.lowlevel import Server
-from pydantic import FileUrl
+from pydantic import AnyUrl
 
 SAMPLE_RESOURCES = {
     "greeting": "Hello! This is a sample text resource.",
@@ -26,7 +26,7 @@ def main(port: int, transport: str) -> int:
     async def list_resources() -> list[types.Resource]:
         return [
             types.Resource(
-                uri=FileUrl(f"file:///{name}.txt"),
+                uri=AnyUrl(f"file:///{name}.txt"),
                 name=name,
                 description=f"A sample text resource named {name}",
                 mimeType="text/plain",
@@ -35,7 +35,9 @@ async def list_resources() -> list[types.Resource]:
         ]
 
     @app.read_resource()
-    async def read_resource(uri: FileUrl) -> str | bytes:
+    async def read_resource(uri: AnyUrl) -> str | bytes:
+        if uri.path is None:
+            raise ValueError(f"Invalid resource path: {uri}")
         name = uri.path.replace(".txt", "").lstrip("/")
 
         if name not in SAMPLE_RESOURCES:

examples/servers/simple-streamablehttp-stateless/mcp_simple_streamablehttp_stateless/__main__.py

@@ -1,4 +1,7 @@
 from .server import main
 
 if __name__ == "__main__":
-    main()
+    # Click will handle CLI arguments
+    import sys
+    
+    sys.exit(main())  # type: ignore[call-arg]

examples/servers/simple-streamablehttp/mcp_simple_streamablehttp/__main__.py

@@ -1,4 +1,4 @@
 from .server import main
 
 if __name__ == "__main__":
-    main()
+    main()  # type: ignore[call-arg]

examples/servers/simple-tool/mcp_simple_tool/__main__.py

@@ -2,4 +2,4 @@
 
 from .server import main
 
-sys.exit(main())
+sys.exit(main())  # type: ignore[call-arg]

pyproject.toml

@@ -85,7 +85,7 @@ Issues = "https://github.com/modelcontextprotocol/python-sdk/issues"
 packages = ["src/mcp"]
 
 [tool.pyright]
-include = ["src/mcp", "tests"]
+include = ["src/mcp", "tests", "examples/servers"]
 venvPath = "."
 venv = ".venv"
 strict = ["src/mcp/**/*.py"]

src/mcp/client/session.py

@@ -201,23 +201,29 @@ async def set_logging_level(self, level: types.LoggingLevel) -> types.EmptyResul
             types.EmptyResult,
         )
 
-    async def list_resources(self) -> types.ListResourcesResult:
+    async def list_resources(
+        self, cursor: str | None = None
+    ) -> types.ListResourcesResult:
         """Send a resources/list request."""
         return await self.send_request(
             types.ClientRequest(
                 types.ListResourcesRequest(
                     method="resources/list",
+                    cursor=cursor,
                 )
             ),
             types.ListResourcesResult,
         )
 
-    async def list_resource_templates(self) -> types.ListResourceTemplatesResult:
+    async def list_resource_templates(
+        self, cursor: str | None = None
+    ) -> types.ListResourceTemplatesResult:
         """Send a resources/templates/list request."""
         return await self.send_request(
             types.ClientRequest(
                 types.ListResourceTemplatesRequest(
                     method="resources/templates/list",
+                    cursor=cursor,
                 )
             ),
             types.ListResourceTemplatesResult,
@@ -278,12 +284,13 @@ async def call_tool(
             request_read_timeout_seconds=read_timeout_seconds,
         )
 
-    async def list_prompts(self) -> types.ListPromptsResult:
+    async def list_prompts(self, cursor: str | None = None) -> types.ListPromptsResult:
         """Send a prompts/list request."""
         return await self.send_request(
             types.ClientRequest(
                 types.ListPromptsRequest(
                     method="prompts/list",
+                    cursor=cursor,
                 )
             ),
             types.ListPromptsResult,
@@ -322,12 +329,13 @@ async def complete(
             types.CompleteResult,
         )
 
-    async def list_tools(self) -> types.ListToolsResult:
+    async def list_tools(self, cursor: str | None = None) -> types.ListToolsResult:
         """Send a tools/list request."""
         return await self.send_request(
             types.ClientRequest(
                 types.ListToolsRequest(
                     method="tools/list",
+                    cursor=cursor,
                 )
             ),
             types.ListToolsResult,

src/mcp/shared/version.py

@@ -1,3 +1,3 @@
 from mcp.types import LATEST_PROTOCOL_VERSION
 
-SUPPORTED_PROTOCOL_VERSIONS: tuple[int, str] = (1, LATEST_PROTOCOL_VERSION)
+SUPPORTED_PROTOCOL_VERSIONS: list[str] = ["2024-11-05", LATEST_PROTOCOL_VERSION]

src/mcp/types.py

@@ -29,7 +29,7 @@
   not separate types in the schema.
 """
 
-LATEST_PROTOCOL_VERSION = "2024-11-05"
+LATEST_PROTOCOL_VERSION = "2025-03-26"
 
 ProgressToken = str | int
 Cursor = str

tests/client/test_list_methods_cursor.py

@@ -0,0 +1,142 @@
+import pytest
+
+from mcp.server.fastmcp import FastMCP
+from mcp.shared.memory import (
+    create_connected_server_and_client_session as create_session,
+)
+
+# Mark the whole module for async tests
+pytestmark = pytest.mark.anyio
+
+
+async def test_list_tools_cursor_parameter():
+    """Test that the cursor parameter is accepted for list_tools.
+    
+    Note: FastMCP doesn't currently implement pagination, so this test
+    only verifies that the cursor parameter is accepted by the client.
+    """
+    server = FastMCP("test")
+
+    # Create a couple of test tools
+    @server.tool(name="test_tool_1")
+    async def test_tool_1() -> str:
+        """First test tool"""
+        return "Result 1"
+
+    @server.tool(name="test_tool_2")
+    async def test_tool_2() -> str:
+        """Second test tool"""
+        return "Result 2"
+
+    async with create_session(server._mcp_server) as client_session:
+        # Test without cursor parameter (omitted)
+        result1 = await client_session.list_tools()
+        assert len(result1.tools) == 2
+
+        # Test with cursor=None
+        result2 = await client_session.list_tools(cursor=None)
+        assert len(result2.tools) == 2
+
+        # Test with cursor as string
+        result3 = await client_session.list_tools(cursor="some_cursor_value")
+        assert len(result3.tools) == 2
+
+        # Test with empty string cursor
+        result4 = await client_session.list_tools(cursor="")
+        assert len(result4.tools) == 2
+
+
+async def test_list_resources_cursor_parameter():
+    """Test that the cursor parameter is accepted for list_resources.
+
+    Note: FastMCP doesn't currently implement pagination, so this test
+    only verifies that the cursor parameter is accepted by the client.
+    """
+    server = FastMCP("test")
+
+    # Create a test resource
+    @server.resource("resource://test/data")
+    async def test_resource() -> str:
+        """Test resource"""
+        return "Test data"
+
+    async with create_session(server._mcp_server) as client_session:
+        # Test without cursor parameter (omitted)
+        result1 = await client_session.list_resources()
+        assert len(result1.resources) >= 1
+
+        # Test with cursor=None
+        result2 = await client_session.list_resources(cursor=None)
+        assert len(result2.resources) >= 1
+
+        # Test with cursor as string
+        result3 = await client_session.list_resources(cursor="some_cursor")
+        assert len(result3.resources) >= 1
+
+        # Test with empty string cursor
+        result4 = await client_session.list_resources(cursor="")
+        assert len(result4.resources) >= 1
+
+
+async def test_list_prompts_cursor_parameter():
+    """Test that the cursor parameter is accepted for list_prompts.
+
+    Note: FastMCP doesn't currently implement pagination, so this test
+    only verifies that the cursor parameter is accepted by the client.
+    """
+    server = FastMCP("test")
+
+    # Create a test prompt
+    @server.prompt()
+    async def test_prompt(name: str) -> str:
+        """Test prompt"""
+        return f"Hello, {name}!"
+
+    async with create_session(server._mcp_server) as client_session:
+        # Test without cursor parameter (omitted)
+        result1 = await client_session.list_prompts()
+        assert len(result1.prompts) >= 1
+
+        # Test with cursor=None
+        result2 = await client_session.list_prompts(cursor=None)
+        assert len(result2.prompts) >= 1
+
+        # Test with cursor as string
+        result3 = await client_session.list_prompts(cursor="some_cursor")
+        assert len(result3.prompts) >= 1
+
+        # Test with empty string cursor
+        result4 = await client_session.list_prompts(cursor="")
+        assert len(result4.prompts) >= 1
+
+
+async def test_list_resource_templates_cursor_parameter():
+    """Test that the cursor parameter is accepted for list_resource_templates.
+
+    Note: FastMCP doesn't currently implement pagination, so this test
+    only verifies that the cursor parameter is accepted by the client.
+    """
+    server = FastMCP("test")
+
+    # Create a test resource template
+    @server.resource("resource://test/{name}")
+    async def test_template(name: str) -> str:
+        """Test resource template"""
+        return f"Data for {name}"
+
+    async with create_session(server._mcp_server) as client_session:
+        # Test without cursor parameter (omitted)
+        result1 = await client_session.list_resource_templates()
+        assert len(result1.resourceTemplates) >= 1
+
+        # Test with cursor=None
+        result2 = await client_session.list_resource_templates(cursor=None)
+        assert len(result2.resourceTemplates) >= 1
+
+        # Test with cursor as string
+        result3 = await client_session.list_resource_templates(cursor="some_cursor")
+        assert len(result3.resourceTemplates) >= 1
+
+        # Test with empty string cursor
+        result4 = await client_session.list_resource_templates(cursor="")
+        assert len(result4.resourceTemplates) >= 1