Version of AIMessage output format to use.
This field is used to roll-out new output formats for chat model AIMessage
responses in a backwards-compatible way.
Supported values:
'v0': AIMessage format as of langchain-openai 0.3.x.'responses/v1': Formats Responses API output items into AIMessage content blocks
(Responses API only)'v1': v1 of LangChain cross-provider standard.langchain-openai 1.0.0Default updated to "responses/v1".