Telegram polling can inherit a stale webhook registration when a deployment
switches transport modes, which leaves getUpdates idle even though the gateway
starts cleanly. Outbound send also treats Telegram retry_after responses as
terminal errors, so brief flood control can drop tool progress and replies.
Constraint: Keep the PR narrowly scoped to upstream/main Telegram adapter behavior
Rejected: Port OpenClaw's broader polling supervisor and offset persistence | too broad for an isolated fix PR
Confidence: high
Scope-risk: narrow
Reversibility: clean
Directive: Polling mode should clear webhook state before starting getUpdates, and send-path retry logic must distinguish flood control from timeouts
Tested: uv run --extra dev pytest tests/gateway/test_telegram_* -q
Not-tested: Live Telegram webhook-to-polling migration and real Bot API 429 behavior
TimedOut is a subclass of NetworkError in python-telegram-bot. The
inner retry loop in send() and the outer _send_with_retry() in base.py
both treated it as a transient connection error and retried — but
send_message is not idempotent. When the request reaches Telegram but
the HTTP response times out, the message is already delivered. Retrying
sends duplicates. Worst case: up to 9 copies (inner 3x × outer 3x).
Inner loop (telegram.py):
- Import TimedOut separately, isinstance-check before generic
NetworkError retry (same pattern as BadRequest carve-out from #3390)
- Re-raise immediately — no retry
- Mark as retryable=False in outer exception handler
Outer loop (base.py):
- Remove 'timeout', 'timed out', 'readtimeout', 'writetimeout' from
_RETRYABLE_ERROR_PATTERNS (read/write timeouts are delivery-ambiguous)
- Add 'connecttimeout' (safe — connection never established)
- Keep 'network' (other platforms still need it)
- Add _is_timeout_error() + early return to prevent plain-text fallback
on timeout errors (would also cause duplicate delivery)
Connection errors (ConnectionReset, ConnectError, etc.) are still
retried — these fail before the request reaches the server.
Credit: tmdgusya (PR #3899), barun1997 (PR #3904) for identifying the
bug and proposing fixes.
Closes#3899, closes#3904.
python-telegram-bot's BadRequest inherits from NetworkError, so the
send() retry loop was catching 'Message thread not found' as a transient
network error and retrying 3 times before silently failing. This killed
all tool progress messages, streaming responses, and typing indicators
when the incoming message carried an invalid message_thread_id.
Now detect BadRequest inside the NetworkError handler:
- 'thread not found' + thread_id set → clear thread_id and retry once
(message still reaches the chat, just without topic threading)
- Other BadRequest errors → raise immediately (permanent, don't retry)
- True NetworkError → retry as before (transient)
252 silent failures in gateway.log traced to this on 2026-03-26.
5 new tests for thread fallback, non-thread BadRequest, no-thread sends,
network retry, and multi-chunk fallback.
