Feature request: support `structured outputs` for `o3-mini` and other openai reasoning models

[elliottower]

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1. Is this request related to a challenge you're experiencing? Tell me about your story.

It looks like you can choose to return a JSON, but can't specify the schema like you can with 4o or other GPT models.

O3:

4o:

2. Additional context or comments

No response

3. Can you help us with this feature?

• [ ] I am interested in contributing to this feature.

[dosubot[bot]]

Hi, @elliottower. I'm Dosu, and I'm helping the Dify team manage their backlog. I'm marking this issue as stale.

Issue Summary:

• Request for structured output support in o3-mini and other OpenAI reasoning models.
• Highlighted absence of JSON schema specification feature, unlike in models like GPT-4o.
• No comments or further activity on the issue since it was opened.

Next Steps:

• Please confirm if this issue is still relevant to the latest version of the Dify repository by commenting on the issue.
• If there is no further activity, the issue will be automatically closed in 15 days.

Thank you for your understanding and contribution!