* fix(agent): merge consecutive assistant messages in repair_message_sequence
Strict OpenAI-compatible providers (DeepSeek v4, Moonshot/Kimi) reject a
replayed history where an assistant message carrying tool_calls is
immediately followed by another assistant message instead of its tool
results — HTTP 400 'An assistant message with tool_calls must be
followed by tool messages...'.
repair_message_sequence (the defensive belt run before every API call)
fixed orphan-tool and consecutive-user shapes but never merged
consecutive assistant messages. Adds a Pass 0 that collapses adjacent
assistant turns into one — union of tool_calls, concatenated content,
carried reasoning_content — covering both reported shapes:
- parallel tool calls split across two assistant turns (#29148)
- content-only assistant followed by tool_calls-only assistant (#49147)
A tool result or user turn between two assistants blocks the merge
(distinct, valid rounds). Runs before Pass 1 so the merged union of
tool_call ids is known to the orphan-tool filter.
Closes#29148, #49147.
Co-authored-by: Bartok9 <danielrpike9@gmail.com>
Co-authored-by: woaini30050 <woaini30050@users.noreply.github.com>
Co-authored-by: weidzhou <weidzhou@users.noreply.github.com>
* fix(agent): exempt codex Responses interim turns from assistant merge
The Pass 0 consecutive-assistant merge collapsed codex_responses interim
turns, which legitimately stay separate — each carries its own encrypted
continuation state (codex_reasoning_items / codex_message_items) that
must replay verbatim. Skip the merge when either side is a codex interim
(has codex_reasoning_items / codex_message_items / finish_reason=='incomplete').
Fixes the slice-2 regression in test_run_agent_codex_responses.py
(test_duplicate_detection_distinguishes_different_codex_{reasoning,message_items}).
---------
Co-authored-by: Bartok9 <danielrpike9@gmail.com>
Co-authored-by: woaini30050 <woaini30050@users.noreply.github.com>
Co-authored-by: weidzhou <weidzhou@users.noreply.github.com>
Follow-up to the #44837 clamp: a min() clamp only fixes cursor overshoot
past the new end of the list. When repair_message_sequence drops/merges
messages at indexes below the cursor, the clamp leaves the cursor pointing
past unflushed rows and the turn-end flush silently skips them.
Extract repair_message_sequence_with_cursor(): snapshot the flushed prefix
by object identity before repair, then recompute the cursor as the count
of surviving flushed messages. Falls back to the clamp when no snapshot is
available. Keeps the safety guard in _flush_messages_to_session_db.
Adds targeted tests for overshoot, before-cursor compaction, no-repair,
bare-agent, and the flush guard.
When empty-response terminal scaffolding fires on a tool-result turn,
_drop_trailing_empty_response_scaffolding left the live history ending at
a bare 'tool' message. The next user input then landed as [...tool, user],
a protocol-invalid sequence that OpenRouter/Opus and other providers
silently fail on (returns empty content). That retriggered the empty-retry
recovery every turn, and recovery flags never hit SQLite (no column for
them), so history kept looking broken on every reload.
Two fixes:
1. Scaffolding strip rewinds the orphan assistant(tool_calls)+tool pair
after popping sentinels. Only fires when scaffolding flags were
actually present, so mid-iteration tool loops are untouched.
2. _repair_message_sequence runs right before every API call as a
defensive belt: drops stray tool messages with unknown tool_call_ids,
merges consecutive user messages so no user input is lost. Does NOT
rewind assistant(tool_calls)+tool+user — that pattern is valid when
the user redirected before the model got its continuation turn.
Repro: session 20260507_044111_fa7e65. Opus-4.7/OpenRouter returned
content-less response after a 42KB execute_code output, nudge+retry
chain exhausted (no fallback configured), terminal sentinel appended,
scaffolding stripped leaving bare tool tail, user typed 'wtf happened..'
and landed as tool→user violation. Every subsequent turn collapsed in
<50ms with the same 3-retry empty chain because the API request itself
was malformed.
Verified live via HTTP mock: pre-fix reproduced 5 api_calls/0.15s exit
'empty_response_exhausted'; post-fix 1 api_call/0.10s exit
'text_response(finish_reason=stop)'. Three-turn session flows cleanly
through the scenario. Full run_agent suite: 1242 passed (0 regressions,
2 pre-existing concurrent_interrupt failures unrelated).
