MCP Status: No live updates when MCP servers connect/disconnect

[ali-nr]

Problem

The MCP status component doesn't update in real-time when MCP servers connect or disconnect. Users must restart Claude Code to see updated status.

Current Behavior

• MCP status is cached for 5 minutes (CACHE_DURATION_MEDIUM)
• Running /mcp to reconnect a server doesn't update the statusline
• Only way to see updated status is to restart Claude Code or wait for cache expiry

Root Cause

• No event-based mechanism to detect MCP state changes
• The statusline polls on a timer, not on MCP events
• Cache invalidation only happens on timeout, not on MCP operations

Proposed Solution

1. Reduced Cache Duration: Reduce MCP cache to 30 seconds for more responsive updates
2. Cache Invalidation Signal: Add mechanism for external tools to signal cache refresh

Files Affected

• lib/mcp.sh - cache duration settings
• lib/cache/operations.sh - cache invalidation mechanism