Function _append_session_context_tail

src/query/query.py:460–492

Place the DeepSeek relocated-volatile sections AFTER the conversation. Wrapped as ambient `` `` context. Merged into the trailing user message when that is a plain user turn (string content, or a content-block list with no ``tool_result``) so the wire keeps strict us

(
    api_messages: list[dict[str, Any]], tail_text: str
)

def _append_session_context_tail(
    api_messages: list[dict[str, Any]], tail_text: str
) -> list[dict[str, Any]]:
    """Place the DeepSeek relocated-volatile sections AFTER the conversation.

    Wrapped as ambient ``<system-reminder>`` context. Merged into the trailing
    user message when that is a plain user turn (string content, or a
    content-block list with no ``tool_result``) so the wire keeps strict
    user/assistant alternation. Otherwise — e.g. the turn ends in a tool result
    (which converts to ``role:tool`` on the wire) — appended as a standalone
    trailing user message, which lands correctly after the tool messages.
    Returns a new list; ``api_messages`` is not mutated.
    """
    reminder = (
        "<system-reminder>\n"
        "Current session/environment context (ambient — not a new user request):\n"
        f"{tail_text}\n"
        "</system-reminder>"
    )
    last = api_messages[-1] if api_messages else None
    if isinstance(last, dict) and last.get("role") == "user":
        content = last.get("content")
        if isinstance(content, str):
            merged = dict(last)
            merged["content"] = f"{content}\n\n{reminder}" if content else reminder
            return [*api_messages[:-1], merged]
        if isinstance(content, list) and not any(
            isinstance(b, dict) and b.get("type") == "tool_result" for b in content
        ):
            merged = dict(last)
            merged["content"] = [*content, {"type": "text", "text": reminder}]
            return [*api_messages[:-1], merged]
    return [*api_messages, {"role": "user", "content": reminder}]


async def _call_model_sync(