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{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Cancelling a Call Tool Request from Client","articleBody":"### Question\n\nHey Team,\nI have a question regarding cancelling the tool call from client when the MCP server is created from `FastMCP` class. \n\nI see the test - [test_cancel_handling](https://github.com/modelcontextprotocol/python-sdk/blob/main/tests/server/test_cancel_handling.py) but this one uses low level server.\n\nMy question is specifically on how we can get the `request_id` which the client needs for cancelling the call tool request on server. \n```\nawait client.send_notification(\n        ClientNotification(\n            CancelledNotification(\n                params=CancelledNotificationParams(\n                    requestId={request_id},\n                    reason=\"Reson\",\n              ),\n          )\n     )\n)\n```\n\nDo we have to get the request id from `call_tool` request? like below?\n\n```py\n  request_id = None\n  mcp = FastMCP(\n      name=\"Simple gRPC Server\",\n  )\n  @mcp.tool()\n  def get_temperature(city: str, ctx: Context[ServerSession, None]) -\u003e float:\n      # fetching request id from context \n      request_id = ctx.request_context.request_id\n      return 22.5\n  \n```\n\nOr is there another way?\n\n### Additional Context\n\n_No response_","author":{"url":"https://github.com/asheshvidyut","@type":"Person","name":"asheshvidyut"},"datePublished":"2025-09-29T06:37:53.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":1},"url":"https://github.com/1410/python-sdk/issues/1410"}