`fastmcp.client.messages`

Classes

`MessageHandler`

This class is used to handle MCP messages sent to the client: notifications and transport-level exceptions. Users can override any of the hooks. Server-initiated requests (ping, sampling, roots) never reach this handler: the stable MCP SDK v2’s message_handler contract only delivers ServerNotification | Exception, so a request has no wire path here. Those are answered through the Client’s dedicated callbacks instead — sampling_handler=, roots=, and elicitation_handler=. Methods:

`dispatch`

dispatch(self, message: Message) -> None

`on_message`

on_message(self, message: Message) -> None

`on_notification`

on_notification(self, message: mcp_types.ServerNotification) -> None

`on_exception`

on_exception(self, message: Exception) -> None

`on_progress`

on_progress(self, message: mcp_types.ProgressNotification) -> None

`on_logging_message`

on_logging_message(self, message: mcp_types.LoggingMessageNotification) -> None

`on_tool_list_changed`

on_tool_list_changed(self, message: mcp_types.ToolListChangedNotification) -> None

`on_resource_list_changed`

on_resource_list_changed(self, message: mcp_types.ResourceListChangedNotification) -> None

`on_prompt_list_changed`

on_prompt_list_changed(self, message: mcp_types.PromptListChangedNotification) -> None

`on_resource_updated`

on_resource_updated(self, message: mcp_types.ResourceUpdatedNotification) -> None

`on_cancelled`

on_cancelled(self, message: mcp_types.CancelledNotification) -> None

⌘I

fastmcp.apps

fastmcp.cli

fastmcp.client

fastmcp.experimental

fastmcp.prompts

fastmcp.resources

fastmcp.server

fastmcp.tools

fastmcp.utilities

messages

`fastmcp.client.messages`

Classes

`MessageHandler`

`dispatch`

`on_message`

`on_notification`

`on_exception`

`on_progress`

`on_logging_message`

`on_tool_list_changed`

`on_resource_list_changed`

`on_prompt_list_changed`

`on_resource_updated`

`on_cancelled`

​fastmcp.client.messages

​Classes

​MessageHandler

​dispatch

​on_message

​on_notification

​on_exception

​on_progress

​on_logging_message

​on_tool_list_changed

​on_resource_list_changed

​on_prompt_list_changed

​on_resource_updated

​on_cancelled

`fastmcp.client.messages`

Classes

`MessageHandler`

`dispatch`

`on_message`

`on_notification`

`on_exception`

`on_progress`

`on_logging_message`

`on_tool_list_changed`

`on_resource_list_changed`

`on_prompt_list_changed`

`on_resource_updated`

`on_cancelled`