diff --git a/python/packages/core/agent_framework/_mcp.py b/python/packages/core/agent_framework/_mcp.py
index d4d5d515dd..88be517bf2 100644
--- a/python/packages/core/agent_framework/_mcp.py
+++ b/python/packages/core/agent_framework/_mcp.py
@@ -228,7 +228,11 @@ class MCPTool:
             name: The name of the MCP tool.
             description: A description of the MCP tool.
             approval_mode: Whether approval is required to run tools.
-            allowed_tools: A collection of tool names to allow.
+            allowed_tools: Optional allow-list of MCP tool names to expose as functions.
+                ``None`` (the default) exposes every tool advertised by the MCP server.
+                An empty collection (``[]``) exposes no tools, which is useful when the
+                server is being used only for prompts or other capabilities. A non-empty
+                collection exposes only the tools whose names appear in it.
             tool_name_prefix: Optional prefix to prepend to exposed MCP function names.
             load_tools: Whether to load tools from the MCP server.
             parse_tool_results: An optional callable with signature
@@ -1592,7 +1596,11 @@ class MCPStdioTool(MCPTool):
                 - A dict with keys `always_require_approval` or `never_require_approval`,
                   followed by a sequence of strings with the names of the relevant tools.
                 A tool should not be listed in both, if so, it will require approval.
-            allowed_tools: A list of tools that are allowed to use this tool.
+            allowed_tools: Optional allow-list of MCP tool names to expose as functions.
+                ``None`` (the default) exposes every tool advertised by the MCP server.
+                An empty collection (``[]``) exposes no tools, which is useful when the
+                server is being used only for prompts or other capabilities. A non-empty
+                collection exposes only the tools whose names appear in it.
             additional_properties: Additional properties.
             args: The arguments to pass to the command.
             env: The environment variables to set for the command.
@@ -1726,7 +1734,11 @@ class MCPStreamableHTTPTool(MCPTool):
                 - A dict with keys `always_require_approval` or `never_require_approval`,
                   followed by a sequence of strings with the names of the relevant tools.
                 A tool should not be listed in both, if so, it will require approval.
-            allowed_tools: A list of tools that are allowed to use this tool.
+            allowed_tools: Optional allow-list of MCP tool names to expose as functions.
+                ``None`` (the default) exposes every tool advertised by the MCP server.
+                An empty collection (``[]``) exposes no tools, which is useful when the
+                server is being used only for prompts or other capabilities. A non-empty
+                collection exposes only the tools whose names appear in it.
             additional_properties: Additional properties.
             terminate_on_close: Close the transport when the MCP client is terminated.
             client: The chat client to use for sampling.
@@ -1901,7 +1913,11 @@ class MCPWebsocketTool(MCPTool):
                 - A dict with keys `always_require_approval` or `never_require_approval`,
                   followed by a sequence of strings with the names of the relevant tools.
                 A tool should not be listed in both, if so, it will require approval.
-            allowed_tools: A list of tools that are allowed to use this tool.
+            allowed_tools: Optional allow-list of MCP tool names to expose as functions.
+                ``None`` (the default) exposes every tool advertised by the MCP server.
+                An empty collection (``[]``) exposes no tools, which is useful when the
+                server is being used only for prompts or other capabilities. A non-empty
+                collection exposes only the tools whose names appear in it.
             additional_properties: Additional properties.
             client: The chat client to use for sampling.
             kwargs: Any extra arguments to pass to the WebSocket client.