[Feature]: do you plan to support "suffix" of "v1/completions"

[qiao-wei]

🚀 The feature, motivation and pitch

do you plan to support "suffix" of "v1/completions"

Alternatives

No response

Additional context

No response

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[DarkLight1337]

Is there a good reason to support it? What is your use case?

[cjackal]

There's working PR #9522 to support suffix (fill-in-the-middle), FYI

[github-actions]

This issue has been automatically marked as stale because it has not had any activity within 90 days. It will be automatically closed if no further activity occurs within 30 days. Leave a comment if you feel this issue should remain open. Thank you!

[mgoin]

This is needed for code completion tasks, otherwise known as fill-in-the-middle or FIM.

For reference this is present in the OpenAI API (with limited support to be fair)

And is available in the DeepSeek API https://api-docs.deepseek.com/api/create-completion

[github-actions]

This issue has been automatically marked as stale because it has not had any activity within 90 days. It will be automatically closed if no further activity occurs within 30 days. Leave a comment if you feel this issue should remain open. Thank you!

[github-actions]

This issue has been automatically closed due to inactivity. Please feel free to reopen if you feel it is still relevant. Thank you!

[Dam930]

This feature is also very important for ProxyAI https://www.tryproxy.io, where we rely on precise suffix handling for structured completions.
At the moment, models tend to ignore or overwrite the suffix, even when it’s meant to delimit or complete the generation (e.g., for JSON, closing brackets, or separators). This makes it hard to enforce predictable outputs, especially when building tools or APIs around the model.

I was wondering if there's any plan to support suffix handling.
Thank you!!