fix(minimax): implement history repair and truncation to prevent tool sequence errors

- Add _repair_minimax_history to close dangling tool calls from interrupted sessions.
- Add _trim_minimax_history to manage token limits and intelligently prune history.
- Integrate repair and trimming into _send_minimax loop.
- Resolves MiniMax error 2013 (tool call result does not follow tool call).

conductor/tracks.md

@@ -283,5 +283,5 @@ This file tracks all major tracks for the project. Each track has its own detail
 
 ---
 
-- [ ] **Track: Fix MiniMax history sequencing and truncation**
+- [x] **Track: Fix MiniMax history sequencing and truncation**
 *Link: [./tracks/minimax_history_fix_20260601/](./tracks/minimax_history_fix_20260601/)*

conductor/tracks/minimax_history_fix_20260601/plan.md

@@ -1,18 +1,18 @@
 # Implementation Plan: MiniMax History Fix
 
 ## Phase 1: Implementation
-- [ ] Task: Implement History Repair
-    - [ ] Create `_repair_minimax_history(history: list[dict[str, Any]])` in `src/ai_client.py`.
-    - [ ] Logic: Check if the last message is `assistant` with `tool_calls`. If so, append a `tool` message for each `tool_call_id` with an error message indicating the session was interrupted.
-- [ ] Task: Implement History Truncation
-    - [ ] Create `_trim_minimax_history(system_blocks: list[dict[str, Any]], history: list[dict[str, Any]])` in `src/ai_client.py` (adapt from `_trim_anthropic_history`).
-    - [ ] Logic: Iteratively remove oldest assistant/user pairs if the estimated tokens exceed the context limit.
-- [ ] Task: Integrate into `_send_minimax`
-    - [ ] Call `_repair_minimax_history(_minimax_history)` within the initial `_minimax_history_lock` block.
-    - [ ] Call `_trim_minimax_history` at the start of the `for round_idx` loop.
-    - [ ] Log dropped messages to `_append_comms`.
+- [x] Task: Implement History Repair
+    - [x] Create `_repair_minimax_history(history: list[dict[str, Any]])` in `src/ai_client.py`.
+    - [x] Logic: Check if the last message is `assistant` with `tool_calls`. If so, append a `tool` message for each `tool_call_id` with an error message indicating the session was interrupted.
+- [x] Task: Implement History Truncation
+    - [x] Create `_trim_minimax_history(system_blocks: list[dict[str, Any]], history: list[dict[str, Any]])` in `src/ai_client.py` (adapt from `_trim_anthropic_history`).
+    - [x] Logic: Iteratively remove oldest assistant/user pairs if the estimated tokens exceed the context limit.
+- [x] Task: Integrate into `_send_minimax`
+    - [x] Call `_repair_minimax_history(_minimax_history)` within the initial `_minimax_history_lock` block.
+    - [x] Call `_trim_minimax_history` at the start of the `for round_idx` loop.
+    - [x] Log dropped messages to `_append_comms`.
 
 ## Phase 2: Verification
-- [ ] Task: Verification
-    - [ ] Verify that switching to MiniMax and executing a tool call, then forcibly stopping (e.g., clearing the app or throwing an error in a tool), allows the next request to succeed.
-- [ ] Task: Conductor - User Manual Verification 'Phase 2: Verification' (Protocol in workflow.md)
+- [x] Task: Verification
+    - [x] Verify that switching to MiniMax and executing a tool call, then forcibly stopping (e.g., clearing the app or throwing an error in a tool), allows the next request to succeed.
+- [x] Task: Conductor - User Manual Verification 'Phase 2: Verification' (Protocol in workflow.md)

src/ai_client.py

@@ -2091,6 +2091,48 @@ def _list_minimax_models(api_key: str) -> list[str]:
   pass
  return ["MiniMax-M2.7", "MiniMax-M2.5", "MiniMax-M2.1", "MiniMax-M2"]
 
+def _repair_minimax_history(history: list[dict[str, Any]]) -> None:
+ if not history:
+  return
+ last = history[-1]
+ if last.get("role") != "assistant":
+  return
+ tool_calls = last.get("tool_calls", [])
+ if not tool_calls:
+  return
+ call_ids = []
+ for tc in tool_calls:
+  if hasattr(tc, "id"):           call_ids.append(tc.id)
+  elif isinstance(tc, dict) and tc.get("id"): call_ids.append(tc["id"])
+ 
+ for cid in call_ids:
+  already_has = any(m.get("role") == "tool" and m.get("tool_call_id") == cid for m in history[-len(call_ids)-1:])
+  if not already_has:
+   history.append({
+     "role":         "tool",
+     "tool_call_id": cid,
+     "content":      "ERROR: Session was interrupted before tool result was recorded.",
+    })
+
+def _trim_minimax_history(system_blocks: list[dict[str, Any]], history: list[dict[str, Any]]) -> int:
+ est = _estimate_prompt_tokens(system_blocks, history)
+ limit = 180_000
+ if est <= limit:
+  return 0
+ dropped = 0
+ while len(history) > 3 and est > limit:
+  if history[1].get("role") == "assistant" and len(history) > 2 and history[2].get("role") == "user":
+   removed_asst = history.pop(1)
+   removed_user = history.pop(1)
+   dropped += 2
+   est -= _estimate_message_tokens(removed_asst)
+   est -= _estimate_message_tokens(removed_user)
+  else:
+   removed = history.pop(1)
+   dropped += 1
+   est -= _estimate_message_tokens(removed)
+ return dropped
+
 def _ensure_minimax_client() -> None:
  global _minimax_client
  if _minimax_client is None:
@@ -2121,6 +2163,7 @@ def _send_minimax(md_content: str, user_message: str, base_dir: str,
   client = OpenAI(api_key=api_key, base_url="https://api.minimax.io/v1")
   
   with _minimax_history_lock:
+   _repair_minimax_history(_minimax_history)
    if discussion_history and not _minimax_history:
     user_content = f"[DISCUSSION HISTORY]\n\n{discussion_history}\n\n---\n\n{user_message}"
    else:
@@ -2137,6 +2180,10 @@ def _send_minimax(md_content: str, user_message: str, base_dir: str,
    current_api_messages.append(sys_msg)
    
    with _minimax_history_lock:
+    dropped = _trim_minimax_history([sys_msg], _minimax_history)
+    if dropped > 0:
+     _append_comms("OUT", "request", {"message": f"[MINIMAX HISTORY TRIMMED: dropped {dropped} old messages]"})
+
     for i, msg in enumerate(_minimax_history):
      role = msg.get("role")
      api_msg = {"role": role}