# Override OpenAI Base URL sends Responses API payload to /chat/completions but expects Chat Completions output

**URL:** <https://forum.cursor.com/t/override-openai-base-url-sends-responses-api-payload-to-chat-completions-but-expects-chat-completions-output/159298>\
**Category:** Bug Reports\
**Tags:** byok, openai\
**Created:** [April 28, 2026, 10:02pm UTC](https://forum.cursor.com/t/override-openai-base-url-sends-responses-api-payload-to-chat-completions-but-expects-chat-completions-output/159298 "2026-04-28T22:02:55Z")\
**Posts on this page:** 1\
**Showing post:** 6

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**Author:** ![deanrie](https://sea3.discourse-cdn.com/cursor1/user_avatar/forum.cursor.com/deanrie/32/1263_2.png) [@deanrie](https://forum.cursor.com/u/deanrie)\
**Post date:** [April 29, 2026, 4:19am UTC](https://forum.cursor.com/t/override-openai-base-url-sends-responses-api-payload-to-chat-completions-but-expects-chat-completions-output/159298/6 "2026-04-29T04:19:56Z")

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Split this topic on April 29, 2026, 4:19am UTC

A post was merged into an existing topic: [Cursor Agent sends Responses API format to /chat/completions endpoint](https://forum.cursor.com/t/cursor-agent-sends-responses-api-format-to-chat-completions-endpoint/153019)

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_[View the full topic](https://forum.cursor.com/t/override-openai-base-url-sends-responses-api-payload-to-chat-completions-but-expects-chat-completions-output/159298)._