--channels plugin receives Telegram messages but notifications never reach the conversation

Description

The official Telegram channels plugin (telegram@claude-plugins-official v0.0.4) connects successfully and polls Telegram, but MCP notifications/claude/channel messages are never injected into the conversation as <channel source="telegram"> tags.

Environment

• Claude Code: 2.1.92
• OS: Windows 11 Pro 10.0.26200
• Runtime: bun 1.3.11
• Plugin: telegram@claude-plugins-official 0.0.4 (user scope, enabled)
• Launch: claude --channels plugin:telegram@claude-plugins-official

Evidence

The harness displays Listening for channel messages from: plugin:telegram@claude-plugins-official at startup.

Running the plugin manually with stdin kept open confirms it works:

$ (sleep 15; echo "quit") | bun run server.ts 2>&1
telegram channel: polling as @just_a_farm_bot
{"method":"notifications/claude/channel","params":{"content":"test message","meta":{"chat_id":"...","message_id":"849","user":"...","ts":"2026-04-04T18:40:57.000Z"}},"jsonrpc":"2.0"}

The plugin polls successfully, receives messages from Telegram, and emits valid JSON-RPC notifications on stdout. But the harness never delivers them to the model.

Steps to reproduce

1. Install: claude plugins install telegram@claude-plugins-official
2. Configure bot token in ~/.claude/channels/telegram/.env
3. Pair a Telegram user
4. Start: claude --channels plugin:telegram@claude-plugins-official
5. Send a message to the bot from Telegram
6. Message never appears in the conversation

Expected behavior

Messages should appear as <channel source="telegram"> tags in the conversation, as they did in earlier Claude Code versions.

Workaround

Polling the Bot API directly via curl to getUpdates works — the bot token and message delivery on Telegram's side are fine. The break is between the plugin's MCP notification and the harness injecting it.