Conversation
When the model parrots the stored compaction handoff summary back to the user (e.g. in response to a simple 'Hello?' after a session with prior compressed context), the raw [CONTEXT COMPACTION] blob leaks into the visible response. Strip the compaction prefix and boilerplate from the response before delivery, so the user sees a clean greeting instead of an opaque internal handoff dump. Closes NousResearch#6212
alt-glitch
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ilyasst
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May 13, 2026
Symptom: local Qwen3.5 via llama-server with --jinja occasionally generates "\nuser\n[<user_name>] ..." past the assistant stop boundary. Hermes formats user messages as "[<user_name>] ..." (gateway/run.py:5692), so the model learned that pattern as the user-turn delimiter; when sampling drifts past the assistant stop, it continues into a plausible user turn. The gateway delivers that verbatim to Telegram — the bot appears to literally echo "[ilyass] nudge" back at the user. Belt + suspenders: - run_agent.py: inject stop sequences ["\nuser\n[", "\n\nuser\n"] into chat_completions api_kwargs after _build_api_kwargs(). Cuts generation at the leak boundary, saving tokens too. Disable via HERMES_DISABLE_USER_PREFIX_STOP=1. - gateway/run.py: post-process final_response with a regex that detects and strips "\nuser\n[<name>] ..." patterns. Safety net for any leak that escapes the stop sequence (e.g., on streaming providers where stop detection differs). Logs a warning when it fires so we can monitor. Related upstream (all open, none merged): NousResearch#6272 (strip [CONTEXT COMPACTION] echoes), NousResearch#19887 (strip leaked template markers from gemma4 tool args), NousResearch#15369 (strip MEDIA directives), NousResearch#18529 (title leaks <thinking>).
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Thanks for the focused gateway safeguard. This is now covered on current
The related #6212 discussion correctly called for a durable boundary around compacted context; current main implements that boundary at the source. |
teknium1
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sweeper:implemented-on-main
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Summary
When a Telegram session has prior compressed context, the model can parrot the stored \[CONTEXT COMPACTION]\ handoff summary back as its response to a simple greeting like \/start\ or \Hello?\. This makes the bot dump an opaque internal handoff blob instead of greeting normally.
Root Cause
The context compressor stores a structured handoff summary prefixed with \[CONTEXT COMPACTION] Earlier turns in this conversation were compacted...\ in the conversation history. When a user re-enters the conversation, the model sees this in its context and may echo it verbatim as the response.
Changes
gateway/run.py - response post-processing (after \�gent_result.get('final_response')\)
Observed Behavior
Before:
After:
The compaction boilerplate is stripped, leaving only any user-facing content the model generated after the echo.
Closes #6212