Problem

When using mcp-remote to connect to VoiceMode Connect (https://voicemode.dev/mcp), the OAuth authorization flow fails with:

Invalid Authorization Request
Error: Invalid redirect URI

The redirect URI generated by mcp-remote is http://localhost:5450/oauth/callback, which voicemode.dev's OAuth server rejects.

Steps to Reproduce

1. Add to .mcp.json:

{"mcpServers": {"voicemode-dev": {"command": "npx", "args": ["-y", "mcp-remote", "https://voicemode.dev/mcp"]}}}

2. Run /mcp in Claude Code → select voicemode-dev → Reconnect
3. OAuth URL generated includes redirect_uri=http://localhost:5450/oauth/callback
4. voicemode.dev returns 'Invalid redirect URI'

Environment

• Claude Code 2.1.85 on Ubuntu 24.04
• mcp-remote 0.1.37
• VoiceMode plugin voicemode@voicemode (connected, working for local voice)
• connect_status MCP tool works — agent registers as online
• But converse fails because local TTS/STT is broken (hardware mic issue)
• Need Connect for remote voice via phone

Expected

voicemode.dev should accept the localhost callback from mcp-remote, or provide an alternative auth flow for CLI agents.

Workaround Attempted

• connect_status(set_presence='available') → returns 'away' (needs TeamCreate)
• Phone web client at app.voicemode.dev shows agent but converse button is greyed out