{"version":"2.1.299","anchor":"mcp-reconnect-can-keep-a-connection-that-has-active-tool-cal","canonical_anchor":"mcp-reconnect-can-keep-a-connection-that-has-active-tool-cal","heading":"Reconnecting an MCP server can keep a connection that is still in use","tier":"notice","area":"MCP","scope":"individual","heads_up":false,"url":"https:\/\/changelogs.core-directive.com\/v\/2.1.299\/e\/mcp-reconnect-can-keep-a-connection-that-has-active-tool-cal","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.299","markdown":"### Reconnecting an MCP server can keep a connection that is still in use\n\nMCP server reconnects now pass `keepConnectionInUse`, so a connection with tool calls still running is kept instead of torn down\n\n**What**\n\nMCP servers are add-on programs that give Claude Code extra tools. Claude Code can reconnect to one when something goes wrong.\n\n- Reconnecting now takes an option, `keepConnectionInUse`, and the reconnect path passes it as true.\n\n- When it is set and the live connection still has tool calls running, the connection is kept instead of closed, and the result is marked `keptConnectionInUse`. Before, a reconnect always closed the existing connection first.\n\n- When a kept connection is connected but its last attempt to list its tools failed (`toolsListError`), the reconnect check now stops early and skips the retry check for failed servers.\n\n**Why**\n\nReconnecting a server while one of its tools is running should no longer cut that tool call off partway. It also changes how Claude Code recovers when a server fails to list its tools.\n\n- Area: MCP\n- Tier: You'll notice\n- Useful: 2\/5\n- Signal: 2\/5\n- Scope: individual\n- Heads-up: no"}