"error_bad_request

[sillyarms]

Where does the bug appear (feature/product)?

Cursor IDE

Describe the Bug

Whenever I try to use cursor chat in the IDE I get an error.

Request ID: 298c5397-3c0f-4c61-9d45-8eadd7bb8e2f
{“error”:“ERROR_BAD_REQUEST”,“details”:{“title”:“Bad request.”,“detail”:“Bad Request”,“isRetryable”:false,“additionalInfo”:{},“buttons”:,“planChoices”:},“isExpected”:true}
ConnectError: [invalid_argument] Error
at _Gc.$endAiConnectTransportReportError (vscode-file://vscode-app/c:/Program%20Files/cursor/resources/app/out/vs/workbench/workbench.desktop.main.js:12154:455960)
at aBo._doInvokeHandler (vscode-file://vscode-app/c:/Program%20Files/cursor/resources/app/out/vs/workbench/workbench.desktop.main.js:12806:22831)
at aBo._invokeHandler (vscode-file://vscode-app/c:/Program%20Files/cursor/resources/app/out/vs/workbench/workbench.desktop.main.js:12806:22573)
at aBo._receiveRequest (vscode-file://vscode-app/c:/Program%20Files/cursor/resources/app/out/vs/workbench/workbench.desktop.main.js:12806:21335)
at aBo._receiveOneMessage (vscode-file://vscode-app/c:/Program%20Files/cursor/resources/app/out/vs/workbench/workbench.desktop.main.js:12806:20152)
at qLt.value (vscode-file://vscode-app/c:/Program%20Files/cursor/resources/app/out/vs/workbench/workbench.desktop.main.js:12806:18244)
at Ee._deliver (vscode-file://vscode-app/c:/Program%20Files/cursor/resources/app/out/vs/workbench/workbench.desktop.main.js:49:2962)
at Ee.fire (vscode-file://vscode-app/c:/Program%20Files/cursor/resources/app/out/vs/workbench/workbench.desktop.main.js:49:3283)
at kvt.fire (vscode-file://vscode-app/c:/Program%20Files/cursor/resources/app/out/vs/workbench/workbench.desktop.main.js:12139:12156)
at MessagePort. (vscode-file://vscode-app/c:/Program%20Files/cursor/resources/app/out/vs/workbench/workbench.desktop.main.js:14803:18433)

Things I have tried that did not work.
Switching from Http/2 to Http/1.1
Switching to several different bot models
Downgrading to 2.1.50

I ran network diagnostics inside the cursor IDE and got all checkmarks.
I am not behind a VPN or corporate network.

Steps to Reproduce

Anytime I ask a question to the chat I get the error and no response

Operating System

Windows 10/11

Current Cursor Version (Menu → About Cursor → Copy)

Version: 2.2.17 (system setup)
VSCode Version: 1.105.1
Commit: cf858ca030e9c9a99ea444ec6efcbcfc40bfda70
Date: 2025-12-11T18:30:06.649Z
Electron: 37.7.0
Chromium: 138.0.7204.251
Node.js: 22.20.0
V8: 13.8.258.32-electron.0
OS: Windows_NT x64 10.0.26100

For AI issues: which model did you use?

Auto

Does this stop you from using Cursor

Yes - Cursor is unusable

[deanrie]

Hey, thanks for the report. The ERROR_BAD_REQUEST often happens for two reasons - MCP servers and the Override OpenAI Base URL toggle.

Please check:

• Settings > MCP - disable all MCP servers and restart Cursor. This has helped before: Always show the error:Bad Request
• Settings > Models > API Keys - if custom keys are enabled, temporarily disable them. Make sure Override OpenAI Base URL is off. There’s a known bug with this toggle: API Keys for ChatGPT and Anthropic Failing
• Create a new chat and see if the error reproduces there.

If it doesn’t help, please send:

• Screenshots of Settings > MCP and Settings > Models > API Keys (showing enabled MCPs and the state of Override OpenAI Base URL)
• Confirmation whether it works in a new chat
• New Request IDs after trying with MCP off and Override Base URL off
• Console errors (Help > Toggle Developer Tools > Console) at the moment of the error

Let me know which step helped.

[sillyarms]

I couldn’t find the MCP setting you were talking about. It wasn’t at the path you mentioned
I toggled the OpenAI Base URL on and off again.

I made a new cursor chat and it works. The old one still does not but I think we are good.

Thanks for the help!