Skip to main content

​
fastmcp.server.middleware.response_limiting

Response limiting middleware for controlling tool response sizes.

​
Classes

​
ResponseLimitingMiddleware

Middleware that limits the response size of tool calls. Intercepts tool call responses and enforces size limits. If a response exceeds the limit, it extracts text content, truncates it, and returns a single TextContent block. Methods:

​
on_call_tool 

on_call_tool(self, context: MiddlewareContext[mt.CallToolRequestParams], call_next: CallNext[mt.CallToolRequestParams, ToolResult]) -> ToolResult
Intercept tool calls and limit response size.