Chrome extension MCP process becomes stale mid-session, kill deregisters tools permanently

Description

The Chrome extension (claude-in-chrome) frequently disconnects during a session. The MCP process (--claude-in-chrome-mcp) caches an OAuth token in memory that expires after ~2 days, but disconnects also happen within shorter sessions.

Symptoms

1. Mid-session disconnect: Chrome extension tools start returning "Browser extension is not connected" after working fine earlier in the same session
2. Screenshot vs other tools: Screenshots fail (go through native host socket) while navigate/click/find still work — then eventually everything fails
3. Kill + reconnect works once: kill <pid> of the --claude-in-chrome-mcp process, then calling a tool again reconnects successfully
4. Second disconnect is permanent: After killing the process a second time (or sometimes after the first kill), ALL chrome tools disappear from the session entirely (Error: No such tool available: mcp__claude-in-chrome__*). Only a full CLI restart recovers them.

Reproduction

1. Start Claude Code session with Chrome extension connected
2. Use chrome tools (navigate, find, click) — works fine
3. Continue session for 30-60 minutes with mixed tool usage (chrome + non-chrome)
4. Chrome tools start failing with "not connected"
5. Kill the --claude-in-chrome-mcp process (ps aux | grep claude-in-chrome-mcp)
6. Chrome tools reconnect and work again
7. After some more time, disconnect happens again
8. Kill process again → tools are now completely deregistered from the session

Expected behavior

• Chrome extension should maintain connection throughout a session
• If disconnected, killing the MCP process and calling a tool should always reconnect
• Tools should never be permanently deregistered from a running session

Environment

• macOS 14 (Darwin 24.6.0)
• Claude Code 2.1.44
• Chrome with Claude extension installed
• Multiple Claude Code sessions sometimes run concurrently (may contribute to socket conflicts)

Workaround

Kill the MCP process with SIGTERM (not SIGKILL). If tools are deregistered, restart the CLI session entirely.