* feat: default to GPT-5.5 medium reasoning
Use OpenAI GPT-5.5 with medium reasoning as the default model and document the completion-token budget semantics for reasoning models.
* fix: use Responses API reasoning config
Pass GPT-5.5 reasoning settings through LangChain's Responses API parameter instead of the Chat Completions-only reasoning_effort field.
* feat: raise GPT-5.5 output budget
Set the default GPT-5.5 output token budget to the model maximum so long-running coding tasks have more room for reasoning and final responses.
* feat: align recursion limit with Deep Agents
Use Deep Agents' default recursion limit so longer coding runs have room to complete without Open SWE imposing a lower cap.
* chore: remove minimal effort level
* chore: reduce max tokens to 64_000
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Co-authored-by: open-swe[bot] <open-swe@users.noreply.github.com>
