Key Takeaways
- Adopt Cline v4.1.1's server-name routing for MCP; it stabilizes tool calls across restarts.
- Key fix: McpHub no longer uses random UIDs, so your MCP servers stay connected even after config edits.
What Changed
Cline v4.1.1 (a VS Code extension for agentic coding) just shipped a quiet but critical fix: the vestigial MCP server-key machinery in McpHub is gone. In previous versions, each MCP server was assigned a random in-memory UID. When you restarted Cline or edited your MCP server list, those UIDs changed—and tool calls could silently route to the wrong server or fail entirely.
Now, native MCP tool calls route by server name instead. That name is stable across sessions and config edits, so the routing table survives restarts and server list changes without breaking.
What It Means For You
If you use MCP servers with Cline (e.g., for filesystem, database, or browser automation), you've probably hit this: you add a server, tweak a config, restart—and suddenly your tools 404 or hit the wrong endpoint. This update eliminates that class of bug.
For Claude Code users, this is a reminder of a broader principle: stable identifiers matter in MCP setups. Random UIDs are a footgun—they break reproducibility and make debugging harder. Server-name routing is the sane alternative.
This also aligns with the MCP community's recent shift toward minimalism (fewer servers, less context bloat). With routing by name, you can confidently remove or reorder servers without worrying about stale references.
Try It Now
- Update Cline to v4.1.1+ (via VS Code marketplace or
code --install-extension cline.cline). - Verify your MCP servers are configured with unique, descriptive names in
cline_mcp_settings.json—avoid generic names like "server1" or "default". - Restart Cline, then run a tool call that uses MCP. Confirm it still works.
- Edit your server list (add/remove a server), restart again, and re-run—routing should hold.
If you're using Claude Code, apply the same principle: keep your MCP server names stable and unique in your config. Claude Code already routes by name, but this fix in Cline highlights how fragile in-memory identifiers can be—so audit your own setup for any similar patterns.
Why This Matters for MCP Users
MCP is exploding—13,000+ servers as of June 2026—and the protocol is moving toward statelessness (the 2026-07-28 spec removed sessions and initialize handshake). In that world, stable routing is non-negotiable. Cline's fix is a small but important step toward production-grade reliability.
It also ties into the security conversation: with 11 CVEs disclosed across 7,000+ MCP instances in July, any improvement in routing stability reduces the chance of misdirected tool calls that could hit unintended targets.
Bottom Line
Cline v4.1.1's server-name routing is a must-have fix if you rely on MCP. Update now, and use stable, descriptive server names to future-proof your setup.
Source: github.com
