Telegram channel plugin: inbound notifications/claude/channel silently dropped

Summary

The Telegram channel plugin (claude-plugins-official/telegram v0.0.4) successfully sends notifications/claude/channel via the MCP stdio transport, but Claude Code never surfaces inbound messages in the conversation. Outbound tools (reply, react, edit_message) work fine.

Reproduction

1. Enable Telegram plugin, configure bot token and allowlist
2. Start Claude Code — plugin connects, MCP tools available
3. Send a message from the allowlisted Telegram user
4. Message never appears as a <channel> tag in the conversation
5. Reproduced across 4+ restarts of Claude Code

Debug evidence

Added logging to server.ts to confirm the plugin side is working correctly:

[2026-03-25T04:11:10.237Z] connecting MCP stdio transport...
[2026-03-25T04:11:10.238Z] MCP stdio transport connected
[2026-03-25T04:12:02.594Z] gate result: deliver for <user_id> in chat <chat_id>
[2026-03-25T04:12:02.595Z] gate passed, delivering "Test" to Claude
[2026-03-25T04:12:02.595Z] notification payload: {"method":"notifications/claude/channel","params":{"content":"Test","meta":{...}}}
[2026-03-25T04:12:02.595Z] notification sent successfully

The MCP notification resolves without error — the transport accepts it — but Claude Code does not inject it into the conversation.

What works

• Bot token is valid (getMe and getUpdates return correctly)
• User ID is in access.json allowFrom
• Gate check passes (action: deliver)
• Outbound: telegram/reply tool sends messages to Telegram successfully
• MCP stdio transport is connected

What doesn't work

• Inbound messages from Telegram never appear in the Claude Code conversation
• No <channel source="telegram" ...> tags are ever rendered

Environment

• Claude Code v2.1.81
• macOS Darwin 25.3.0
• Plugin runtime: bun
• Plugin version: claude-plugins-official/telegram 0.0.4