Problem:
Modern LLMs (GPT-5.4, Claude, Gemini) produce markdown-heavy responses with
numbered lists, headers, and nested formatting. The Telegram channel's
_markdown_to_telegram_html() converter has gaps that leave these poorly
formatted:
1. Numbered lists (1. 2. 3.) have zero handling — sent as raw text
2. Headers (# Title) are stripped to plain text, losing visual hierarchy
3. Mid-stream edits send raw markdown (users see **bold** and ### headers
while the response generates, before the final HTML conversion)
Root Cause:
_markdown_to_telegram_html() handles bullets (- *) but skips numbered lists
entirely. Headers are stripped of # but not given any emphasis. The streaming
path in send_delta() sends buf.text as-is during mid-stream edits (plain
text, no parse_mode) — only the final _stream_end edit converts to HTML.
Fix:
1. Headers now render as <b>bold</b> in the final HTML (using placeholder
markers that survive HTML escaping, restored after all other processing)
2. Numbered lists are normalized (extra whitespace after the dot is cleaned)
3. New _strip_md_block() function strips markdown syntax for readable
plain-text preview during streaming mid-edits
The final _stream_end HTML conversion is unchanged — it still produces
full HTML with parse_mode=HTML. Only the intermediate edits are improved.
Tests:
Added 10 new tests covering:
- Headers converting to bold HTML
- Numbered list preservation and whitespace normalization
- Headers with HTML special characters
- Mixed formatting (headers + bullets + numbers + bold)
- _strip_md_block for inline formatting, headers, bullets, numbers, links
- Streaming mid-edit markdown stripping (initial send + edit)
- Fix critical plain-text fallback that was sending raw HTML tags to
users: keep raw markdown available for the fallback path
- Extract TELEGRAM_HTML_MAX_LEN (4096) constant to replace hardcoded
magic number and document the difference from TELEGRAM_MAX_MESSAGE_LEN
- Add fallback to _send_text for extra HTML chunks when HTML parse fails
- Add missing @pytest.mark.asyncio decorator on
test_send_delta_stream_end_html_expansion_does_not_overflow
Cherry-picked from #3311 (stutiredboy). Streaming edits called
edit_message_text(text=buf.text) without chunking, so once accumulated
deltas crossed Telegram's 4096-char limit an ongoing stream would fail
with BadRequest.
Extracts _flush_stream_overflow helper that edits the first chunk in
place, sends any middle chunks, and re-anchors the buffer to a new
message for the tail so subsequent deltas keep streaming.
Co-Authored-By: stutiredboy <stutiredboy@users.noreply.github.com>
Cherry-picked from #3316 (himax12). When streaming completes in send_delta(),
the code was splitting raw markdown text by 4000, then converting to HTML.
The markdown-to-HTML conversion adds 10-33% characters, which could push
the result over Telegram's 4096 character limit.
The fix converts markdown to HTML first, then splits by 4096 (actual Telegram
limit), ensuring the edited message always fits.
Fixes#3315
Audited all channel implementations for overly broad exception handling
that causes retry amplification or silent message loss during network
errors. This is the same class of bug as #3050 (Telegram _send_text).
Fixes by channel:
Telegram (send_delta):
- _stream_end path used except Exception for HTML edit fallback
- Network errors (TimedOut, NetworkError) triggered redundant plain
text edit, doubling connection demand during pool exhaustion
- Changed to except BadRequest, matching the _send_text fix
Discord:
- send() caught all exceptions without re-raising
- ChannelManager._send_with_retry() saw successful return, never retried
- Messages silently dropped on any send failure
- Added raise after error logging
DingTalk:
- _send_batch_message() returned False on all exceptions including
network errors — no retry, fallback text sent unnecessarily
- _read_media_bytes() and _upload_media() swallowed transport errors,
causing _send_media_ref() to cascade through doomed fallback attempts
- Added except httpx.TransportError handlers that re-raise immediately
WeChat:
- Media send failure triggered text fallback even for network errors
- During network issues: 3×(media + text) = 6 API calls per message
- Added specific catches: TimeoutException/TransportError re-raise,
5xx HTTPStatusError re-raises, 4xx falls back to text
QQ:
- _send_media() returned False on all exceptions
- Network errors triggered fallback text instead of retry
- Added except (aiohttp.ClientError, OSError) that re-raises
Tests: 331 passed (283 existing + 48 new across 5 channel test files)
Fixes: #3054
Related: #3050, #3053
Previously _send_text() caught all exceptions (except Exception) when
sending HTML-formatted messages, falling back to plain text even for
network errors like TimedOut and NetworkError. This caused connection
demand to double during pool exhaustion scenarios (3 retries × 2
fallback attempts = 6 calls per message instead of 3).
Now only catches BadRequest (HTML parse errors), letting network errors
propagate immediately to the retry layer where they belong.
Fixes: HKUDS/nanobot#3050
Forward static location pins as [location: lat, lon] content so the
agent can respond to geo messages and pass coordinates to MCP tools.
ClosesHKUDS/nanobot#2909
Use dream_log and dream_restore in Telegram's bot command menu so command registration succeeds, while still accepting the original dream-log and dream-restore forms in chat. Keep the internal command routing unchanged and add coverage for the alias normalization path.
Make channel delivery failures raise consistently so retry policy lives in ChannelManager rather than being split across individual channels. Tighten Telegram stream finalization, clarify sendMaxRetries semantics, and align the docs with the behavior the system actually guarantees.
