diff --git a/letta/services/mcp_manager.py b/letta/services/mcp_manager.py
index 173c909e..0f2ad4a8 100644
--- a/letta/services/mcp_manager.py
+++ b/letta/services/mcp_manager.py
@@ -419,6 +419,9 @@ class MCPManager:
         """
         # Create base MCPServer object
         if isinstance(server_config, StdioServerConfig):
+            # Check if stdio MCP servers are disabled (not suitable for multi-tenant deployments)
+            if tool_settings.mcp_disable_stdio:
+                raise ValueError("MCP stdio servers are disabled. Set MCP_DISABLE_STDIO=false to enable them.")
             mcp_server = MCPServer(server_name=server_config.server_name, server_type=server_config.type, stdio_config=server_config)
         elif isinstance(server_config, SSEServerConfig):
             mcp_server = MCPServer(
@@ -832,6 +835,9 @@ class MCPManager:
             server_config = SSEServerConfig(**server_config.model_dump())
             return AsyncFastMCPSSEClient(server_config=server_config, oauth=oauth, agent_id=agent_id)
         elif server_config.type == MCPServerType.STDIO:
+            # Check if stdio MCP servers are disabled (not suitable for multi-tenant deployments)
+            if tool_settings.mcp_disable_stdio:
+                raise ValueError("MCP stdio servers are disabled. Set MCP_DISABLE_STDIO=false to enable them.")
             server_config = StdioServerConfig(**server_config.model_dump())
             return AsyncStdioMCPClient(server_config=server_config, oauth_provider=None, agent_id=agent_id)
         elif server_config.type == MCPServerType.STREAMABLE_HTTP:
diff --git a/letta/services/mcp_server_manager.py b/letta/services/mcp_server_manager.py
index 8bd8534d..f1981a03 100644
--- a/letta/services/mcp_server_manager.py
+++ b/letta/services/mcp_server_manager.py
@@ -516,6 +516,9 @@ class MCPServerManager:
         """
         # Create base MCPServer object
         if isinstance(server_config, StdioServerConfig):
+            # Check if stdio MCP servers are disabled (not suitable for multi-tenant deployments)
+            if tool_settings.mcp_disable_stdio:
+                raise ValueError("MCP stdio servers are disabled. Set MCP_DISABLE_STDIO=false to enable them.")
             mcp_server = MCPServer(server_name=server_config.server_name, server_type=server_config.type, stdio_config=server_config)
         elif isinstance(server_config, SSEServerConfig):
             mcp_server = MCPServer(
@@ -1003,6 +1006,9 @@ class MCPServerManager:
             server_config = SSEServerConfig(**server_config.model_dump())
             return AsyncFastMCPSSEClient(server_config=server_config, oauth=oauth, agent_id=agent_id)
         elif server_config.type == MCPServerType.STDIO:
+            # Check if stdio MCP servers are disabled (not suitable for multi-tenant deployments)
+            if tool_settings.mcp_disable_stdio:
+                raise ValueError("MCP stdio servers are disabled. Set MCP_DISABLE_STDIO=false to enable them.")
             server_config = StdioServerConfig(**server_config.model_dump())
             return AsyncStdioMCPClient(server_config=server_config, oauth_provider=None, agent_id=agent_id)
         elif server_config.type == MCPServerType.STREAMABLE_HTTP:
diff --git a/letta/settings.py b/letta/settings.py
index 19899cd0..10297603 100644
--- a/letta/settings.py
+++ b/letta/settings.py
@@ -37,7 +37,16 @@ class ToolSettings(BaseSettings):
     mcp_list_tools_timeout: float = 30.0
     mcp_execute_tool_timeout: float = 60.0
     mcp_read_from_config: bool = False  # if False, will throw if attempting to read/write from file
-    mcp_disable_stdio: bool = False
+    mcp_disable_stdio: bool = Field(
+        default=True,
+        description=(
+            "Disable MCP stdio server type. When True (default), creating or connecting to "
+            "MCP servers using stdio transport will fail. Stdio MCP servers spawn local "
+            "processes, which is not suitable for multi-tenant or shared server deployments. "
+            "Set to False for local or single-user deployments where stdio-based MCP servers "
+            "are needed (e.g., running local tools via npx or uvx)."
+        ),
+    )
 
     @property
     def modal_sandbox_enabled(self) -> bool: