fix: refresh tool and prompt caches after remote MCP server reconnect#2246
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dgageot merged 1 commit intodocker:mainfrom Mar 25, 2026
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After a successful reconnect in watchConnection, eagerly call refreshToolCache so the runtime picks up the new server's tools and the toolsChangedHandler is invoked. Without this, the runtime kept using its stale copy of the tool list. Add TestRemoteReconnectRefreshesTools to verify that when a remote MCP server restarts with a different set of tools the Toolset returns the updated tools and notifies the handler. Extract startMCPServer and allocateAddr test helpers to reduce duplication across reconnect tests. Fixes docker#2244 Assisted-By: docker-agent
rumpl
approved these changes
Mar 25, 2026
trungutt
approved these changes
Mar 25, 2026
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After a remote MCP server restarts, the tool/prompt caches were invalidated but the runtime was never notified to re-fetch. This caused stale tools to be returned after reconnection.
Changes
pkg/tools/mcp/mcp.go: CallrefreshToolCacheandrefreshPromptCacheinwatchConnectionafter a successful restart so the runtime picks up the new server's tools/prompts.pkg/tools/mcp/reconnect_test.go: AddTestRemoteReconnectRefreshesToolswhich verifies that after a server restarts with different tools,Tools()returns the new set andtoolsChangedHandleris called. ExtractstartMCPServer/allocateAddrhelpers to reduce duplication.Fixes #2244