Enable Alternative Completions (n) When Using Structured Outputs in OpenAI Models

[dbuos]

Checked

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Feature request

LangChain currently does not support retrieving multiple alternative completions (n > 1) when using structured outputs with OpenAI models. This capability would be beneficial for applications that require multiple possible outputs for ranking, ensemble methods, or diversity-based selection.

Expected Behavior:
• Return multiple structured outputs in response, each representing an alternative completion.

Motivation

•	Generating multiple structured responses for reranking.
•	Exploring diverse structured outputs to increase robustness in decision-making systems.

Proposal (If applicable)

No response