diff --git a/pkgs/development/python-modules/fastmcp/default.nix b/pkgs/development/python-modules/fastmcp/default.nix
index 017b9894c07c..996f00ccc253 100644
--- a/pkgs/development/python-modules/fastmcp/default.nix
+++ b/pkgs/development/python-modules/fastmcp/default.nix
@@ -158,6 +158,9 @@ buildPythonPackage (finalAttrs: {
     # AssertionError: assert len(caplog.records) == 1
     "test_log"
 
+    #  assert [TextContent(...e, meta=None)] == [TextContent(...e, meta=None)]
+    "test_read_resource_tool_works"
+
     # fastmcp.exceptions.ToolError: Unknown tool
     "test_multi_client_with_logging"
     "test_multi_client_with_elicitation"
diff --git a/pkgs/development/python-modules/mcp/default.nix b/pkgs/development/python-modules/mcp/default.nix
index 9df48a47c598..b8536ececaa5 100644
--- a/pkgs/development/python-modules/mcp/default.nix
+++ b/pkgs/development/python-modules/mcp/default.nix
@@ -40,16 +40,16 @@
   requests,
 }:
 
-buildPythonPackage rec {
+buildPythonPackage (finalAttrs: {
   pname = "mcp";
-  version = "1.25.0";
+  version = "1.26.0";
   pyproject = true;
 
   src = fetchFromGitHub {
     owner = "modelcontextprotocol";
     repo = "python-sdk";
-    tag = "v${version}";
-    hash = "sha256-fSQCvKaNMeCzguM2tcTJJlAeZQmzSJmbfEK35D8pQcs=";
+    tag = "v${finalAttrs.version}";
+    hash = "sha256-TGkAyuBcIstL2BCZYBWoi7PhnhoBvap67sLWGe0QUoU=";
   };
 
   # time.sleep(0.1) feels a bit optimistic and it has been flaky whilst
@@ -106,7 +106,7 @@ buildPythonPackage rec {
     pytestCheckHook
     requests
   ]
-  ++ lib.concatAttrValues optional-dependencies;
+  ++ lib.flatten (builtins.attrValues finalAttrs.passthru.optional-dependencies);
 
   disabledTests = [
     # attempts to run the package manager uv
@@ -152,7 +152,7 @@ buildPythonPackage rec {
   __darwinAllowLocalNetworking = true;
 
   meta = {
-    changelog = "https://github.com/modelcontextprotocol/python-sdk/releases/tag/${src.tag}";
+    changelog = "https://github.com/modelcontextprotocol/python-sdk/releases/tag/${finalAttrs.src.tag}";
     description = "Official Python SDK for Model Context Protocol servers and clients";
     homepage = "https://github.com/modelcontextprotocol/python-sdk";
     license = lib.licenses.mit;
@@ -161,4 +161,4 @@ buildPythonPackage rec {
       josh
     ];
   };
-}
+})