Where does the bug appear (feature/product)? Cursor IDE Describe the Bug When using OpenAI API Key + Override OpenAI Base URL (custom OpenAI-compatible endpoint / BYOK), attaching any image to a chat causes the request to fail with: “Unauthorized User Openai API key” Text-only chats work perfec…

Guys how is that possible no update on this more than a month? @deanrie can you please inform the team this is really important.

Unfortunately, this may push me back to Codex. I even built and open-sourced Cursor-OpenAI-BYOK-Bridge to work around Cursor’s OpenAI-compatible BYOK issue where Agent requests are sent to /v1/chat/completions, but the payload is closer to the Responses API format. The bridge translates those reque…

@xiatian11 , thanks for the detailed report and for sharing the bridge project. Confirmed, it’s the same root issue that’s being discussed in this thread. Multimodal requests don’t even reach your bridge because the key validation goes from our backend directly to api.openai.com, bypassing the Base U…

Just adding to the people saying it’s a hard blocker to using cursor. Looking into switching IDEs

Hitting the same issue :confused: Anyone found a good alternative yet? my plan is about to end.

Hey @sertdev , I’ve added you to the confirmations list. Honestly, there’s still no fix and I can’t share an ETA. There’s also no user-side workaround yet. The key validation goes straight from our backend to api.openai.com, skipping the Base URL override, so proxies or bridges won’t intercept it. I…

Hey, there’s still no update on the fix, and I can’t give an honest ETA. @sertdev @Mehmet_Baykar @rid I’m seeing confirmations from multiple users in the thread, and I get that this is a hard blocker for you, especially with subscription cancellations. This has real impact, and I escalated the issu…

@sertdev I can understand your frustration, but I assure you I’m a person and not a bot. I personally read every post and respond to all of them personally as an employee of this company. You can run my response through AI detection software for as long as you want, but that would just be a distract…

ok :neutral_face::neutral_face::neutral_face:

[Bug] Images/vision completely broken with OpenAI BYOK + custom endpoint override (Unauthorized error)

Support Bug Reports

Colin (Colin) June 29, 2026, 4:47pm 78

Thanks for confirming @Mehmet_Baykar and @nunesmatheus!

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[Bug] Images/vision completely broken with OpenAI BYOK + custom endpoint override (Unauthorized error)

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