Repoint tests and examples off removed deprecations

Replaces FastMCP.as_proxy() helper calls with create_proxy(), rewrites the
mount() as_proxy=/prefix= kwarg tests to plain mount() (the params are gone),
and deletes deprecation-only tests for as_proxy() and remove_tool().

examples/in_memory_proxy_example.py

@@ -3,7 +3,7 @@ This example demonstrates how to set up and use an in-memory FastMCP proxy.
 
 It illustrates the pattern:
 1. Create an original FastMCP server with some tools.
-2. Create a proxy FastMCP server using ``FastMCP.as_proxy(original_server)``.
+2. Create a proxy FastMCP server using ``create_proxy(original_server)``.
 3. Use another Client to connect to the proxy server (in-memory) and interact with the original server's tools through the proxy.
 """
 
@@ -13,6 +13,7 @@ from mcp.types import TextContent
 
 from fastmcp import FastMCP
 from fastmcp.client import Client
+from fastmcp.server import create_proxy
 
 
 class EchoService:
@@ -38,9 +39,9 @@ async def main():
     # 2. Proxy Server Creation
     print("\nStep 2: Creating the Proxy Server (InMemoryProxy)...")
     print(
-        f"          (Using FastMCP.as_proxy to wrap '{original_server.name}' directly)"
+        f"          (Using create_proxy to wrap '{original_server.name}' directly)"
     )
-    proxy_server = FastMCP.as_proxy(original_server, name="InMemoryProxy")
+    proxy_server = create_proxy(original_server, name="InMemoryProxy")
     print(
         f"   -> Proxy Server '{proxy_server.name}' created, proxying '{original_server.name}'."
     )

examples/mount_example.py

@@ -63,9 +63,9 @@ def check_app_status() -> dict[str, str]:
 
 
 # Mount sub-applications
-app.mount(server=weather_app, prefix="weather")
+app.mount(server=weather_app, namespace="weather")
 
-app.mount(server=news_app, prefix="news")
+app.mount(server=news_app, namespace="news")
 
 
 async def get_server_details():

tests/client/test_openapi.py

@@ -6,6 +6,7 @@ from mcp_types import TextResourceContents
 
 from fastmcp import Client, FastMCP
 from fastmcp.client.transports import SSETransport, StreamableHttpTransport
+from fastmcp.server import create_proxy
 from fastmcp.server.providers.openapi import MCPType, RouteMap
 from fastmcp.utilities.tests import run_server_async
 
@@ -63,7 +64,7 @@ async def sse_server():
 @pytest.fixture
 async def proxy_server(shttp_server: str):
     """Start a proxy server."""
-    proxy = FastMCP.as_proxy(StreamableHttpTransport(shttp_server))
+    proxy = create_proxy(StreamableHttpTransport(shttp_server))
     async with run_server_async(proxy, transport="http") as url:
         yield url
 

tests/client/test_stdio.py

@@ -46,10 +46,12 @@ class TestParallelCalls:
         return script_file
 
     async def test_parallel_calls(self, stdio_script):
+        from fastmcp.server import create_proxy
+
         backend_transport = PythonStdioTransport(script_path=stdio_script)
         backend_client = Client(transport=backend_transport)
 
-        proxy = FastMCP.as_proxy(backend=backend_client, name="PROXY")
+        proxy = create_proxy(backend_client, name="PROXY")
 
         count = 10
 

tests/server/middleware/test_middleware_nested.py

@@ -8,6 +8,7 @@ from mcp.server.context import ServerRequestContext
 
 from fastmcp import Client, FastMCP
 from fastmcp.exceptions import ToolError
+from fastmcp.server import create_proxy
 from fastmcp.server.context import Context
 from fastmcp.server.middleware import CallNext, Middleware, MiddlewareContext
 from fastmcp.tools.base import ToolResult
@@ -475,7 +476,7 @@ class TestProxyServer:
     ):
         # proxy server will have its tools listed as well as called in order to
         # apply transforms and filters prior to the call.
-        proxy_server = FastMCP.as_proxy(mcp_server, name="Proxy Server")
+        proxy_server = create_proxy(mcp_server, name="Proxy Server")
         async with Client(proxy_server) as client:
             await client.call_tool("add", {"a": 1, "b": 2})
 
@@ -492,7 +493,7 @@ class TestProxyServer:
     ):
         """Tests that tags on remote FastMCP servers are visible to middleware
         via proxy. See https://github.com/PrefectHQ/fastmcp/issues/1300"""
-        proxy_server = FastMCP.as_proxy(mcp_server, name="Proxy Server")
+        proxy_server = create_proxy(mcp_server, name="Proxy Server")
 
         TAGS = []
 

tests/server/mount/test_mount.py

@@ -9,6 +9,7 @@ from mcp_types import TextContent
 from fastmcp import FastMCP
 from fastmcp.client import Client
 from fastmcp.client.transports import SSETransport
+from fastmcp.server import create_proxy
 from fastmcp.tools.base import Tool
 from fastmcp.tools.tool_transform import TransformedTool
 
@@ -272,7 +273,7 @@ class TestMultipleServerMount:
         )
 
         # Create a proxy server that will fail to connect
-        unreachable_proxy = FastMCP.as_proxy(
+        unreachable_proxy = create_proxy(
             unreachable_client, name="unreachable_proxy"
         )
 

tests/server/mount/test_proxy.py

@@ -6,8 +6,8 @@ from contextlib import asynccontextmanager
 from fastmcp import FastMCP
 from fastmcp.client import Client
 from fastmcp.client.transports import FastMCPTransport
+from fastmcp.server import create_proxy
 from fastmcp.server.providers import FastMCPProvider
-from fastmcp.server.providers.proxy import FastMCPProxy
 from fastmcp.server.providers.wrapped_provider import _WrappedProvider
 from fastmcp.server.transforms import Namespace
 
@@ -25,7 +25,7 @@ class TestProxyServer:
             return f"Data for {query}"
 
         # Create proxy server
-        proxy_server = FastMCP.as_proxy(FastMCPTransport(original_server))
+        proxy_server = create_proxy(FastMCPTransport(original_server))
 
         # Mount proxy server
         main_app = FastMCP("MainApp")
@@ -45,7 +45,7 @@ class TestProxyServer:
         original_server = FastMCP("OriginalServer")
 
         # Create proxy server
-        proxy_server = FastMCP.as_proxy(FastMCPTransport(original_server))
+        proxy_server = create_proxy(FastMCPTransport(original_server))
 
         # Mount proxy server
         main_app = FastMCP("MainApp")
@@ -74,7 +74,7 @@ class TestProxyServer:
             return json.dumps({"api_key": "12345"})
 
         # Create proxy server
-        proxy_server = FastMCP.as_proxy(FastMCPTransport(original_server))
+        proxy_server = create_proxy(FastMCPTransport(original_server))
 
         # Mount proxy server
         main_app = FastMCP("MainApp")
@@ -96,7 +96,7 @@ class TestProxyServer:
             return f"Welcome, {name}!"
 
         # Create proxy server
-        proxy_server = FastMCP.as_proxy(FastMCPTransport(original_server))
+        proxy_server = create_proxy(FastMCPTransport(original_server))
 
         # Mount proxy server
         main_app = FastMCP("MainApp")
@@ -108,10 +108,10 @@ class TestProxyServer:
         # The message should contain our welcome text
 
 
-class TestAsProxyKwarg:
+class TestMountProviderStructure:
-    """Test the as_proxy kwarg."""
+    """Test the provider structure produced by mounting."""
 
-    async def test_as_proxy_defaults_false(self):
+    async def test_mount_wraps_in_fastmcp_provider(self):
         mcp = FastMCP("Main")
         sub = FastMCP("Sub")
 
@@ -133,53 +133,6 @@ class TestAsProxyKwarg:
         tools = await mcp.list_tools()
         assert {t.name for t in tools} == {"sub_sub_tool"}
 
-    async def test_as_proxy_false(self):
-        mcp = FastMCP("Main")
-        sub = FastMCP("Sub")
-
-        @sub.tool
-        def sub_tool() -> str:
-            return "test"
-
-        mcp.mount(sub, "sub", as_proxy=False)
-
-        # Index 1 because LocalProvider is at index 0
-        provider = mcp.providers[1]
-        # Provider is wrapped with Namespace transform
-        assert isinstance(provider, _WrappedProvider)
-        assert len(provider._transforms) == 1
-        assert isinstance(provider._transforms[0], Namespace)
-        # Inner provider is FastMCPProvider
-        assert isinstance(provider._inner, FastMCPProvider)
-        assert provider._inner.server is sub
-        # Verify namespace is applied
-        tools = await mcp.list_tools()
-        assert {t.name for t in tools} == {"sub_sub_tool"}
-
-    async def test_as_proxy_true(self):
-        mcp = FastMCP("Main")
-        sub = FastMCP("Sub")
-
-        @sub.tool
-        def sub_tool() -> str:
-            return "test"
-
-        mcp.mount(sub, "sub", as_proxy=True)
-
-        # Index 1 because LocalProvider is at index 0
-        provider = mcp.providers[1]
-        # Provider is wrapped with Namespace transform
-        assert isinstance(provider, _WrappedProvider)
-        assert len(provider._transforms) == 1
-        assert isinstance(provider._transforms[0], Namespace)
-        # Inner provider is FastMCPProvider wrapping a proxy
-        assert isinstance(provider._inner, FastMCPProvider)
-        assert provider._inner.server is not sub
-        assert isinstance(provider._inner.server, FastMCPProxy)
-        # Verify namespace is applied
-        tools = await mcp.list_tools()
-        assert {t.name for t in tools} == {"sub_sub_tool"}
-
     async def test_lifespan_server_mounted_directly(self):
         """Test that servers with lifespan are mounted directly (not auto-proxied).
 
@@ -214,10 +167,10 @@ class TestAsProxyKwarg:
         tools = await mcp.list_tools()
         assert {t.name for t in tools} == {"sub_sub_tool"}
 
-    async def test_as_proxy_ignored_for_proxy_mounts_default(self):
+    async def test_mounting_a_proxy_preserves_the_proxy(self):
         mcp = FastMCP("Main")
         sub = FastMCP("Sub")
-        sub_proxy = FastMCP.as_proxy(FastMCPTransport(sub))
+        sub_proxy = create_proxy(FastMCPTransport(sub))
 
         mcp.mount(sub_proxy, "sub")
 
@@ -231,45 +184,11 @@ class TestAsProxyKwarg:
         assert isinstance(provider._inner, FastMCPProvider)
         assert provider._inner.server is sub_proxy
 
-    async def test_as_proxy_ignored_for_proxy_mounts_false(self):
+    async def test_mounts_have_live_link(self):
-        mcp = FastMCP("Main")
-        sub = FastMCP("Sub")
-        sub_proxy = FastMCP.as_proxy(FastMCPTransport(sub))
-
-        mcp.mount(sub_proxy, "sub", as_proxy=False)
-
-        # Index 1 because LocalProvider is at index 0
-        provider = mcp.providers[1]
-        # Provider is wrapped with Namespace transform
-        assert isinstance(provider, _WrappedProvider)
-        assert len(provider._transforms) == 1
-        assert isinstance(provider._transforms[0], Namespace)
-        # Inner provider is FastMCPProvider
-        assert isinstance(provider._inner, FastMCPProvider)
-        assert provider._inner.server is sub_proxy
-
-    async def test_as_proxy_ignored_for_proxy_mounts_true(self):
-        mcp = FastMCP("Main")
-        sub = FastMCP("Sub")
-        sub_proxy = FastMCP.as_proxy(FastMCPTransport(sub))
-
-        mcp.mount(sub_proxy, "sub", as_proxy=True)
-
-        # Index 1 because LocalProvider is at index 0
-        provider = mcp.providers[1]
-        # Provider is wrapped with Namespace transform
-        assert isinstance(provider, _WrappedProvider)
-        assert len(provider._transforms) == 1
-        assert isinstance(provider._transforms[0], Namespace)
-        # Inner provider is FastMCPProvider
-        assert isinstance(provider._inner, FastMCPProvider)
-        assert provider._inner.server is sub_proxy
-
-    async def test_as_proxy_mounts_still_have_live_link(self):
         mcp = FastMCP("Main")
         sub = FastMCP("Sub")
 
-        mcp.mount(sub, "sub", as_proxy=True)
+        mcp.mount(sub, "sub")
 
         assert len(await mcp.list_tools()) == 0
 
@@ -294,7 +213,7 @@ class TestAsProxyKwarg:
         def hello():
             return "hi"
 
-        mcp.mount(sub, as_proxy=True)
+        mcp.mount(sub)
 
         assert lifespan_check == []
 

tests/server/providers/proxy/test_proxy_client.py

@@ -12,6 +12,7 @@ from mcp_types import (
 from pydantic import BaseModel, Field
 
 from fastmcp import Client, Context, FastMCP
+from fastmcp.server import create_proxy
 from fastmcp.client.elicitation import ElicitRequestParams, ElicitResult
 from fastmcp.client.logging import LogMessage
 from fastmcp.client.sampling import RequestContext, SamplingMessage, SamplingParams
@@ -88,7 +89,7 @@ async def proxy_server(fastmcp_server: FastMCP):
     """
     A proxy server that forwards interactions with the proxy client to the given fastmcp server.
     """
-    return FastMCP.as_proxy(ProxyClient(fastmcp_server))
+    return create_proxy(ProxyClient(fastmcp_server))
 
 
 class TestProxyClient:
@@ -377,7 +378,7 @@ class TestProxyClient:
             else:
                 return f"Elicitation {result.action}"
 
-        proxy_server = FastMCP.as_proxy(ProxyClient(fastmcp_server))
+        proxy_server = create_proxy(ProxyClient(fastmcp_server))
 
         # Test that elicitation works correctly through the proxy
         async def elicitation_handler(
@@ -407,16 +408,16 @@ class TestProxyClient:
         # Create a disconnected client (should use fresh sessions per request)
         base_client = Client(fastmcp_server)
 
-        # Test both as_proxy convenience method and direct client_factory usage
+        # Test both create_proxy convenience function and direct client_factory usage
-        proxy_via_as_proxy = FastMCP.as_proxy(base_client)
+        proxy_via_create_proxy = create_proxy(base_client)
         proxy_via_factory = FastMCPProxy(client_factory=base_client.new)
 
         # Verify the proxies are created successfully - this tests the client factory pattern
-        assert proxy_via_as_proxy is not None
+        assert proxy_via_create_proxy is not None
         assert proxy_via_factory is not None
 
         # Verify they have the expected client factory behavior
-        assert hasattr(proxy_via_as_proxy, "_local_provider")
+        assert hasattr(proxy_via_create_proxy, "_local_provider")
         assert hasattr(proxy_via_factory, "_local_provider")
 
     async def test_connected_proxy_client_uses_fresh_sessions(
@@ -464,7 +465,7 @@ def roots_backend_server():
 
 @pytest.fixture
 async def roots_proxy_server(roots_backend_server: FastMCP):
-    return FastMCP.as_proxy(ProxyClient(roots_backend_server))
+    return create_proxy(ProxyClient(roots_backend_server))
 
 
 class TestProxyServerInitiatedForwardingNonTool:

tests/server/providers/proxy/test_proxy_server.py

@@ -198,38 +198,6 @@ def test_create_proxy_with_url():
     assert client.transport.url == "http://example.com/mcp/"
 
 
-# --- Deprecated as_proxy tests (verify backwards compatibility) ---
-
-
-async def test_as_proxy_deprecated_with_server(fastmcp_server):
-    """FastMCP.as_proxy should work but emit deprecation warning."""
-    import warnings
-
-    with warnings.catch_warnings(record=True) as w:
-        warnings.simplefilter("always")
-        proxy = FastMCP.as_proxy(fastmcp_server)
-        assert len(w) == 1
-        assert issubclass(w[0].category, DeprecationWarning)
-        assert "create_proxy" in str(w[0].message)
-
-    async with Client(proxy) as client:
-        result = await client.call_tool("greet", {"name": "Test"})
-        assert result.data == "Hello, Test!"
-
-
-def test_as_proxy_deprecated_with_url():
-    """FastMCP.as_proxy should work but emit deprecation warning."""
-    import warnings
-
-    with warnings.catch_warnings(record=True) as w:
-        warnings.simplefilter("always")
-        proxy = FastMCP.as_proxy("http://example.com/mcp/")
-        assert len(w) == 1
-        assert issubclass(w[0].category, DeprecationWarning)
-
-    assert isinstance(proxy, FastMCPProxy)
-
-
 async def test_proxy_with_async_client_factory():
     """FastMCPProxy should accept an async client_factory."""
 

tests/server/test_server.py

@@ -1,5 +1,4 @@
 import os
-import warnings
 from pathlib import Path
 from tempfile import TemporaryDirectory
 from textwrap import dedent
@@ -161,37 +160,6 @@ class TestLocalProviderProperty:
         assert not any(p.name == "my_prompt" for p in prompts)
 
 
-class TestRemoveToolDeprecation:
-    async def test_remove_tool_emits_deprecation_warning(self):
-        mcp = FastMCP()
-
-        @mcp.tool
-        def my_tool() -> str:
-            return "result"
-
-        with warnings.catch_warnings(record=True) as w:
-            warnings.simplefilter("always")
-            mcp.remove_tool("my_tool")
-
-            assert len(w) == 1
-            assert issubclass(w[0].category, DeprecationWarning)
-            assert "local_provider" in str(w[0].message)
-
-    async def test_remove_tool_still_works(self):
-        mcp = FastMCP()
-
-        @mcp.tool
-        def my_tool() -> str:
-            return "result"
-
-        with warnings.catch_warnings():
-            warnings.simplefilter("ignore", DeprecationWarning)
-            mcp.remove_tool("my_tool")
-
-        tools = await mcp.list_tools()
-        assert not any(t.name == "my_tool" for t in tools)
-
-
 class TestResourcePrefixMounting:
     """Test resource prefixing in mounted servers."""
 

tests/tools/tool_transform/test_tool_transform.py

@@ -719,8 +719,9 @@ class TestProxy:
     @pytest.fixture
     def proxy_server(self, mcp_server: FastMCP) -> FastMCP:
         from fastmcp.client.transports import FastMCPTransport
+        from fastmcp.server import create_proxy
 
-        proxy = FastMCP.as_proxy(FastMCPTransport(mcp_server))
+        proxy = create_proxy(FastMCPTransport(mcp_server))
         return proxy
 
     async def test_transform_proxy(self, proxy_server: FastMCP):