--channels flag never matches plugin server identifier — channel notifications always skipped

Summary

The Telegram plugin's inbound message delivery is completely broken. Channel push notifications are silently dropped by the harness due to an identifier-matching bug in the --channels flag implementation. The check_messages polling tool (the only workaround) was removed in plugin v0.0.6, leaving zero working paths for inbound messages.

This affects every --channels value — including the harness's own internal identifier for the server. The comparison itself is broken.

Environment

• OS: Windows 11 Home 10.0.26200
• Claude Code: Tested on 2.1.104 and 2.1.117
• Plugin: telegram@claude-plugins-official v0.0.6
• Plugin runtime: Bun 1.3.11

The Bug

The harness resolves the Telegram MCP server's internal identifier as plugin:telegram:telegram. When the plugin sends a notifications/claude/channel MCP notification, the harness checks whether this identifier is in the --channels list. This check always fails, even when the exact string plugin:telegram:telegram is passed via --channels.

MCP log proof

Every session since ~April 8 logs this at startup (4ms after connection):

{"debug":"Channel notifications skipped: server plugin:telegram:telegram not in --channels list for this session"}

This appears regardless of what --channels value is passed:

| Invocation | Result |
|---|---|
| claude (no flag) | "not in --channels list" |
| claude --channels plugin:telegram@claude-plugins-official | "not in --channels list" |
| claude --channels plugin:telegram:telegram | "not in --channels list" |
| claude --channels telegram | "not in --channels list" |

The identifier in the error message (plugin:telegram:telegram) is the harness's own internal name for this server. Passing that exact string back via --channels still fails. The comparison itself is broken.

Contrast with working session

The last working session (March 27, 2026) used an older harness version that auto-registered channels:

March 27 (WORKING):
  Line 2: "Successfully connected to undefined server in 227ms"
  Line 4: "Channel notifications registered"

April 8+ (BROKEN):
  Line 2: "Successfully connected (transport: stdio) in 300ms"
  Line 4: "Channel notifications skipped: server plugin:telegram:telegram not in --channels list"

The old harness didn't resolve a server identifier ("undefined server"). It auto-registered channel notifications for any MCP server declaring the experimental: { 'claude/channel': {} } capability. A harness update between March 27 and April 8 introduced the --channels opt-in requirement, but the identifier matching was implemented incorrectly.

Where the Bug Lives

The bug is in the Claude Code harness (compiled binary), in the code path that:

1. Receives a notifications/claude/channel MCP notification from a connected server
2. Looks up the server's identifier (resolves to plugin:telegram:telegram)
3. Checks whether that identifier appears in the parsed --channels CLI argument
4. This check returns false even when the strings are identical

Possible root causes:

• The --channels argument may not be parsed at all (the list is always empty)
• The CLI argument parser may be splitting on : and mangling the value
• The comparison may use a different normalization than the identifier resolution
• The --channels feature may be gated behind a flag that silently disables it

The log message "Channel notifications skipped: server {id} not in --channels list for this session" should be searchable in the harness source.

Secondary Issue: check_messages Tool Removed

On April 8, even though push notifications were already broken, inbound messages still worked because the plugin had a check_messages tool that Claude could call via cron to poll for queued messages:

April 8 MCP log:
  Line 4: "Channel notifications skipped" (push broken)
  Line 5: "Calling MCP tool: check_messages" (poll workaround working)
  Line 6: "Tool 'check_messages' completed successfully in 19ms"

Plugin v0.0.6 removed check_messages, leaving only: reply, react, download_attachment, edit_message. With push broken AND poll removed, there is no path for inbound messages.

Recommendation: Re-add check_messages to the official plugin as a fallback for environments where channel notifications don't work.

Timeline

| Date | Harness | Plugin | Push | Poll | Inbound |
|---|---|---|---|---|---|
| March 27 | Old (auto-register) | Pre-0.0.6 | Working | Working | Working |
| April 8 | New (--channels required) | Pre-0.0.6 | Broken | Working | Working (via poll) |
| April 11+ | New | v0.0.6 | Broken | Removed | Dead |
| April 21 | New (2.1.104 + 2.1.117) | v0.0.6 | Broken (all values tried) | Removed | Dead |

What Was Tried (exhaustive)

1. Plugin reinstall (x2)
2. Nuclear reset of channel state directory
3. Claude Code downgrade 2.1.117 to 2.1.104
4. --channels plugin:telegram@claude-plugins-official
5. --channels plugin:telegram:telegram (exact match to harness identifier)
6. --channels plugin:telegram
7. --channels telegram
8. Verified plugin connects fine (tools work, outbound replies work)
9. Verified plugin sends notifications (no error in plugin's catch handler)
10. Read plugin source — notification code is correct
11. Compared working vs broken MCP logs — confirmed harness-side regression

Workaround

Patched check_messages back into the local plugin source (server.ts). The plugin bot queues inbound messages in memory, and a CronCreate job calls check_messages every 3 minutes. This restores inbound messaging with a 0-3 minute delay. Fragile — any plugin auto-update overwrites the patch.

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 via /telegram:access
4. Start: claude --channels plugin:telegram:telegram
5. Check MCP log — will show "Channel notifications skipped"
6. Send a message from Telegram — bot receives it (typing indicator shows), but nothing appears in Claude Code

Key Files

• MCP logs: %LOCALAPPDATA%\claude-cli-nodejs\Cache\C--Users-timeb\mcp-logs-plugin-telegram-telegram\
• Plugin source: %USERPROFILE%\.claude\plugins\cache\claude-plugins-official\telegram\0.0.6\server.ts
• Channel state: %USERPROFILE%\.claude\channels\telegram\