Summary

Telegram direct-message turns that end with no visible final reply can still emit a synthetic user-facing bubble like "No added response from me." instead of staying silent.

Reproduction shape

This reproduces when:

• surface = telegram
• conversation type = direct / DM
• the turn ends without a visible final reply
• there is no dispatch error and no non-silent delivery failure

A real incident produced repeated Telegram DM bubbles such as:

• No added response from me.
• followed later by a recovered background-task completion message

Root cause

There are two pieces that combine into the leak:

1. extensions/telegram/src/bot-message-dispatch.ts

   • in the !queuedFinal && !sentFallback && !dispatchError && !deliverySummary.delivered path
   • the adapter synthesizes [{ text: "NO_REPLY" }]
   • then immediately routes it through outbound delivery

2. src/infra/outbound/payloads.ts + silent-reply policy defaults

   • direct conversations default to silentReply.direct = "disallow"
   • direct conversations default to silentReplyRewrite.direct = true
   • so the synthetic NO_REPLY is rewritten into visible filler text like No added response from me.

That means an intentionally silent Telegram DM turn is converted into misleading chatter.

Why this is a bug

The adapter already has a separate fallback path for actual failures:

• dispatch error
• or non-silent delivery failure / skip

This no-visible-response path is different: it can represent an intentionally silent turn. In that case the Telegram adapter should not fabricate a user-visible message.

Expected behavior

For Telegram DMs:

• if a turn ends with no visible final reply and no actual error,
• keep the turn truly silent
• do not synthesize a NO_REPLY fallback bubble
• status reaction state should complete as a normal handled turn, not as an error

Additional note

The current test suite explicitly encodes the buggy behavior in extensions/telegram/src/bot-message-dispatch.test.ts by expecting a DM no-visible-response turn to be rewritten through silent-reply fallback.

Proposed fix

In extensions/telegram/src/bot-message-dispatch.ts:

• suppress synthetic silent-reply fallback for Telegram direct turns
• treat the silent turn as handled
• keep group behavior unchanged unless the projected fallback is already empty

I have a PR ready with:

• source fix in extensions/telegram/src/bot-message-dispatch.ts
• regression test update in extensions/telegram/src/bot-message-dispatch.test.ts