[Bug] Tool descriptions silently truncated without user notification or retrieval mechanism

Bug Description
I'd like to report a tool-loading issue in Cowork and Claude Code: if a tool's description is
too big, it gets silently truncated. The truncation isn't surfaced in the UI in any way, and the
agent has no way to retrieve the full version.

To reproduce: install the Fibery MCP server and try the query tool — its description is ~8k
chars and gets cut mid-sentence around 2k.

The only workaround we found was adding a companion MCP tool that returns the full description
as a tool-call response. That's awkward because the agent doesn't always realize the description
was truncated and so doesn't know to call it.

Surprisingly, this issue does NOT happen in regular Claude Chat (non-Cowork) — the same MCP
server delivers the full description there.

Environment Info

• Platform: darwin
• Terminal: WezTerm
• Version: 2.1.112
• Feedback ID: 4f8a6e09-5d7a-4ad8-99d3-fd0f2e177101