MCP servers from plugins fail to start in agent team split panes

Bug Description

When using agent teams with iTerm2 split panes, plugin-provided MCP servers fail to start in spawned teammate panes. The status line shows 1 MCP server failed · /mcp.

Environment

• Claude Code with CLAUDE_CODE_EXPERIMENTAL_AGENT_TEAMS=1
• iTerm2 with it2 CLI (v0.2.0)
• macOS Darwin 25.2.0
• Plugin: claude-mem@thedotmack (provides mcp-search MCP server)

Steps to Reproduce

1. Have a plugin installed that provides an MCP server (e.g., claude-mem with mcp-search)
2. Enable agent teams: "CLAUDE_CODE_EXPERIMENTAL_AGENT_TEAMS": "1" in settings
3. Spawn a team with teammates using TeamCreate + Task tool
4. Teammates spawn in iTerm2 split panes
5. Each pane shows 1 MCP server failed in the status line

Root Cause

The plugin's MCP server is configured with a path using ${CLAUDE_PLUGIN_ROOT}:

{
  "mcpServers": {
    "mcp-search": {
      "type": "stdio",
      "command": "${CLAUDE_PLUGIN_ROOT}/scripts/mcp-server.cjs"
    }
  }
}

The CLAUDE_PLUGIN_ROOT environment variable does not appear to be propagated correctly to the child agent processes spawned in split panes, causing the MCP server command to fail.

Expected Behavior

Plugin MCP servers should start successfully in agent teammate panes, with CLAUDE_PLUGIN_ROOT (and any other required env vars) properly propagated to child processes.

Actual Behavior

MCP server fails silently in each agent pane. The agents still function for built-in tools (Read, Edit, Grep, etc.) but cannot access plugin-provided MCP tools.

Impact

Low — agents can complete most tasks without plugin MCP servers. But plugins that provide critical MCP tools (e.g., memory search, specialized APIs) would be unavailable to teammates.

🤖 Generated with Claude Code