Where does the bug appear (feature/product)?
Cursor IDE
Describe the Bug
I encountered this issue when using a custom API key with the GPT 5.6 series; the problem occurred on version 3.12.17
It seems that none of the GPT models work after configuring a custom API key
Steps to Reproduce
This issue occurs when selecting the GPT-5.6 model after configuring a custom OpenAI API key
Operating System
Windows 10/11
Version Information
Version: 3.12.17 (system setup)
VS Code Extension API: 1.128.0
Commit: 0fb762053c34788bb7760d5673f8a6d4c8589d50
Date: 2026-07-17T02:53:53.006Z
Layout: IDE
Build Type: Stable
Release Track: Default
Electron: 40.10.3
Chromium: 144.0.7559.236
Node.js: 24.15.0
V8: 14.4.258.32-electron.0
xterm.js: 6.1.0-beta.256
OS: Windows_NT x64 10.0.26200
For AI issues: which model did you use?
gpt 5.6
For AI issues: add Request ID with privacy disabled
Request ID: e8aac837-b480-4361-82a1-70f4247cc625
{“error”:“ERROR_BAD_REQUEST”,“details”:{“title”:“Bad Request”,“detail”:“This model does not support custom API keys.”,“isRetryable”:false,“additionalInfo”:{},“buttons”:,“planChoices”:,“analyticsMetadata”:{“actionRequired”:“config”}},“isExpected”:true}
Bad Request This model does not support custom API keys.
ActionRequiredError: Bad Request This model does not support custom API keys.
at mAf (vscode-file://vscode-app/c:/Program%20Files/cursor/resources/app/out/vs/workbench/workbench.desktop.main.js:9278:6259)
at zYi (vscode-file://vscode-app/c:/Program%20Files/cursor/resources/app/out/vs/workbench/workbench.desktop.main.js:9278:5410)
at mTp (vscode-file://vscode-app/c:/Program%20Files/cursor/resources/app/out/vs/workbench/workbench.desktop.main.js:9279:11972)
at Object.classify (vscode-file://vscode-app/c:/Program%20Files/cursor/resources/app/out/vs/workbench/workbench.desktop.main.js:9279:16501)
at vAf (vscode-file://vscode-app/c:/Program%20Files/cursor/resources/app/out/vs/workbench/workbench.desktop.main.js:9279:5856)
at async lYo.runWithSharedTurnRunner (vscode-file://vscode-app/c:/Program%20Files/cursor/resources/app/out/vs/workbench/workbench.desktop.main.js:9279:15853)
at async YH.runAgentLoop (vscode-file://vscode-app/c:/Program%20Files/cursor/resources/app/out/vs/workbench/workbench.desktop.main.js:15854:72761)
at async q1a.streamFromAgentBackend (vscode-file://vscode-app/c:/Program%20Files/cursor/resources/app/out/vs/workbench/workbench.desktop.main.js:15882:14489)
at async q1a.getAgentStreamResponse (vscode-file://vscode-app/c:/Program%20Files/cursor/resources/app/out/vs/workbench/workbench.desktop.main.js:15882:24576)
at async eDe.submitChatMaybeAbortCurrent (vscode-file://vscode-app/c:/Program%20Files/cursor/resources/app/out/vs/workbench/workbench.desktop.main.js:9452:2491)
Does this stop you from using Cursor
Sometimes - I can sometimes use Cursor