Remove unused imports (F401) and duplicate/shadowed import
redefinitions (F811) across the codebase using ruff's safe
autofixes. No behavioral changes -- imports only.
- ~1400 safe autofixes applied across 644 files (net -1072 lines)
- __init__.py re-exports preserved (excluded from F401 removal so
public re-export surfaces stay intact)
- Re-exports that are imported or monkeypatched by tests but look
unused in their defining module are kept with explicit # noqa:
F401 (gateway/run.py load_dotenv; run_agent re-exports from
agent.message_sanitization, agent.context_compressor,
agent.retry_utils, agent.prompt_builder, agent.process_bootstrap,
agent.codex_responses_adapter)
- Unsafe F841 (unused-variable) fixes deliberately skipped -- those
can change behavior when the RHS has side effects
- ruff lints remain disabled in pyproject.toml (only PLW1514 is
selected); this is a one-time cleanup, not a config change
Verification:
- python -m compileall: clean
- pytest --collect-only: all 27161 tests collect (zero import errors)
- core entry points import clean (run_agent, model_tools, cli,
toolsets, hermes_state, batch_runner, gateway)
- static scan: every name any test imports directly from an edited
module still resolves
Some providers (Xiaomi MiMo, some Alibaba endpoints, a long tail of
OpenAI-compatible servers) follow the OpenAI spec strictly and require
tool message `content` to be a string — they reject our list-type
content (text + image_url parts) with HTTP 400 'text is not set' /
'tool message content must be a string'.
Instead of an allowlist of known-good providers (maintenance burden,
guaranteed to miss aggregators like OpenRouter where the underlying
model determines support, not the aggregator name), this lands a
reactive recovery:
1. New `FailoverReason.multimodal_tool_content_unsupported` with a
small pattern list covering the common 400 wordings.
2. `AIAgent._try_strip_image_parts_from_tool_messages` walks the API
message list, downgrades any `role:tool` message whose content is
list-with-image to a plain text summary (preserves text parts) in
place, AND records the active (provider, model) in a session-scoped
`_no_list_tool_content_models` set.
3. `_tool_result_content_for_active_model` short-circuits to a text
summary when (provider, model) is in the cache — so after the first
400 + retry, subsequent screenshots in the same session skip the
round trip entirely.
4. Retry hook in `agent.conversation_loop` mirrors the existing
`image_too_large` recovery: detect the reason, run the helper,
retry once, fall through to the normal error path if no list-type
tool content was actually present.
Cache is transient (per-session) by design — next session retries in
case the provider added support, no persistent state to maintain.
Fixes#27344. Closes#27351 (allowlist approach superseded by reactive
recovery).