feat: migrate from FastMCP v2 to v3

pyproject.toml

@@ -169,7 +169,7 @@ dependencies = [
   "ast-grep-py>=0.40.3",
   # * ================ Server and MCP Server Framework ==================*
   # fastmcp is the core MCP server framework
-  "fastmcp>=2.14.0",
+  "fastmcp>=3.0.0,<4.0.0",
   # just used for types but we need them at runtime for Pydantic models
   "mcp>=1.23.3",
   # Runs the core admin/management server

src/codeweaver/server/mcp/server.py

@@ -17,7 +17,8 @@
 
 from fastmcp import FastMCP
 from fastmcp.client.transports import StreamableHttpTransport
-from fastmcp.server.proxy import FastMCPProxy, ProxyClient
+from fastmcp.server import create_proxy
+from fastmcp.server.providers.proxy import FastMCPProxy, ProxyClient
 from fastmcp.tools import Tool
 from lateimport import lateimport
 
@@ -300,6 +301,10 @@ def _setup_server[TransportT: Literal["stdio", "streamable-http"]](
     run_args = mutable_args.pop("run_args", {})
     # Remove transport from args - it's not a FastMCP constructor parameter
     mutable_args.pop("transport", None)
+    # FastMCP v3: include_tags/exclude_tags are no longer constructor parameters.
+    # Extract them here and apply via app.enable()/app.disable() after construction.
+    include_tags: set[str] | None = mutable_args.pop("include_tags", None)
+    exclude_tags: set[str] | None = mutable_args.pop("exclude_tags", None)
 
     # Always use default middleware classes for this transport
     from codeweaver.server.mcp.middleware import default_middleware_for_transport
@@ -314,6 +319,11 @@ def _setup_server[TransportT: Literal["stdio", "streamable-http"]](
     )
     app = register_tools(app)
     app = register_middleware(app, cast(list[type[McpMiddleware]], middleware), middleware_opts)
+    # FastMCP v3: Apply tag-based visibility filtering using the new enable()/disable() API
+    if exclude_tags:
+        app.disable(tags=exclude_tags)
+    if include_tags:
+        app.enable(tags=include_tags, only=True)
     if is_http:
         from codeweaver.server.mcp.state import CwMcpHttpState
 
@@ -349,16 +359,23 @@ async def create_stdio_server(
         stdio_settings = DictView(FastMcpServerSettingsDict(**cast(dict, stdio_settings)))
     else:
         stdio_settings = _get_fastmcp_settings_map(http=False)
-    app = _setup_server(stdio_settings, transport="stdio")
+    # Derive the stdio server name directly from settings instead of constructing
+    # a full FastMCP app instance just to access `app.name`.
+    stdio_name = cast(str | None, stdio_settings.get("name"))
     if settings and (http_settings := settings.get("mcp_server")) is not UNSET:
         http_settings = DictView(FastMcpServerSettingsDict(**cast(dict, http_settings)))
     else:
         http_settings = _get_fastmcp_settings_map(http=True)
-        run_args = http_settings.get("run_args", {})
+    run_args = http_settings.get("run_args", {})
     resolved_host = host or run_args.get("host", LOCALHOST)
     resolved_port = port or run_args.get("port", DEFAULT_MCP_PORT)
     url = f"http://{resolved_host}:{resolved_port}{http_settings.get('path', MCP_ENDPOINT)}"
-    return app.as_proxy(backend=ProxyClient(transport=StreamableHttpTransport(url=url)))
+    # FastMCP v3: Replace app.as_proxy() with create_proxy()
+    # create_proxy() takes a target (URL, transport, client, etc.) and settings
+    return create_proxy(
+        target=ProxyClient(transport=StreamableHttpTransport(url=url)),
+        name=stdio_name or cast(str, http_settings.get("name", "codeweaver-mcp")),
+    )
 
 
 async def create_http_server(