* fix(middlewares): end length-capped turns cleanly, prevent todo re-engagement, annotate write_file budget
When a model hits its per-response output cap (finish_reason=length) while
emitting a write_file tool call, ModelLengthFinishReasonMiddleware suppresses
the truncated call and stamps model_length_termination. TodoMiddleware must
not re-engage (jump_to=model) on such a capped turn -- doing so re-emits the
same oversized call into the same cap, producing up to 3 futile responses
with junk fragments instead of a clean truncation notice.
Changes:
- TodoMiddleware.after_model: skip completion reminder jump when
additional_kwargs.model_length_termination is present (follows the existing
deerflow_error_fallback precedent).
- ModelLengthFinishReasonMiddleware: always append the length notice when
tool calls were suppressed, even when partial text survived (collapses the
visible-content ternary). Fixes a latent bug in append_visible_text that
silently dropped string content.
- tools.get_available_tools: annotate write_file's model-visible description
with the model's configured max_tokens output budget. Guarded extraction
safely handles missing or non-numeric tokens, and the tool is cloned via
model_copy to keep module-level singletons immutable across assemblies and
prevent guidance leakage to unbudgeted models.
- release_policy_parameters() updated for both middlewares.
- AGENTS.md chain entries (#20, #35) and module docstrings updated within
AG002 guidance limits.
- Tests: 8 new/focused unit tests + 1 updated pin + 1 real create_agent()
integration test reproducing the incident (thread b1723286).
* fix(tools): use effective model cap for write_file guidance
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Co-authored-by: Willem Jiang <willem.jiang@gmail.com>
