_compact_old_tool_returns ran in before_model_request, whose result core
assigns back onto ctx.state.message_history, so the trim reached
all_messages() and every host that persists a thread. It now runs in
wrap_model_request, which operates on a detached list: the model sees the
trimmed history, the host keeps what it retrieved.
Content attached to a ToolReturn arrives as its own UserPromptPart in the
same ModelRequest as the ToolReturnPart, so the turn-boundary scan read an
image-bearing search result as a new user turn and discarded evidence
retrieved earlier in the same turn. _is_user_turn() now requires a request
with no tool returns.
Page images on a replaced return stay. Dropping them with their text bounds
context growth, but a follow-up about a figure already shown ("what colour
is that box?") carries no terms that could retrieve it again: measured on
gemma4-26b against two ORB figures, removing the image turned both answers
into "I cannot find enough information", and keeping it answers correctly.
Bounding that growth needs to preserve cited figures, which is a separate
change.
The replacement notice no longer claims citations remain in state;
_clear_invocation_state has cleared them by then.
5d76461b9f