Calude 4 not working for past 24h

[baka_kun]

Describe the Bug

Claude 4 sonnet not working

see this “Request ID: 5cc83b5d-f617-4d10-bb01-4f42aa3b90b5
{“error”:“ERROR_OPENAI”,“details”:{“title”:“Unable to reach the model provider”,“detail”:“We’re having trouble connecting to the model provider. This might be temporary - please try again in a moment.”,“additionalInfo”:{},“buttons”:},“isExpected”:false}”

Steps to Reproduce

I have tried using it and it keeps saying no!

Screenshots / Screen Recordings

Operating System

MacOS

Current Cursor Version (Menu → About Cursor → Copy)

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Does this stop you from using Cursor

Yes - Cursor is unusable

[deanrie]

Hey, does it happen in new chats?

[cutalion (Alexander)]

I have the same error when I start chat with o3 and then switch to claude-4-sonnet.
Conversation is not long.

I usually use o3 for better planning and claude for implementation. In my experience, it works better without loosing the context over time.

Fresh chat with claude works.

[nodesyn]

Anthropic has been having connectivity issues the past 24 hours. That might be at least part of the reason why.

[scupit]

I’ve been encountering the same issue for the past 24 hours or so. Here’s some additional context I’ve observed you may find helpful:

• I have the ultra plan and have made light to moderate use of AI for the past few days. Rate limiting is likely not the issue.

• This error doesn’t occur immediately in new chats (first message). However, it can happen as early as the second message in a newly created chat.

• The error only occurs after either o3 or o4-mini make a tool call. Specifically, after o3 or o4-mini execute a file Read, I am unable to use other models (gpt 4.1, sonnet 4, sonnet 4 thinking) for the next message. I’m unsure if this is the case for other tools.

• Once the error occurs, I am only able to use o3 or o4-mini for the rest of the chat.

• No other models cause this error; If I use sonnet 4 for the whole chat, the error will not occur.

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Here are my error details:

Request ID: 45b3920b-5d1a-48d8-9698-4c8aa5a1886b

{
  "error": "ERROR_OPENAI",
  "details": {
    "title": "Unable to reach the model provider",
    "detail": "We're having trouble connecting to the model provider. This might be temporary - please try again in a moment.",
    "additionalInfo": {},
    "buttons": []
  },
  "isExpected": false
}

ConnectError: [unavailable] Error
    at x9a.$endAiConnectTransportReportError (vscode-file://vscode-app/c:/Users/MyWindowsUser/AppData/Local/Programs/cursor/resources/app/out/vs/workbench/workbench.desktop.main.js:4757:223764)
    at hir.S (vscode-file://vscode-app/c:/Users/MyWindowsUser/AppData/Local/Programs/cursor/resources/app/out/vs/workbench/workbench.desktop.main.js:492:17741)
    at hir.Q (vscode-file://vscode-app/c:/Users/MyWindowsUser/AppData/Local/Programs/cursor/resources/app/out/vs/workbench/workbench.desktop.main.js:492:17519)
    at hir.M (vscode-file://vscode-app/c:/Users/MyWindowsUser/AppData/Local/Programs/cursor/resources/app/out/vs/workbench/workbench.desktop.main.js:492:16607)
    at hir.L (vscode-file://vscode-app/c:/Users/MyWindowsUser/AppData/Local/Programs/cursor/resources/app/out/vs/workbench/workbench.desktop.main.js:492:15708)
    at Bwt.value (vscode-file://vscode-app/c:/Users/MyWindowsUser/AppData/Local/Programs/cursor/resources/app/out/vs/workbench/workbench.desktop.main.js:492:14500)
    at ve.B (vscode-file://vscode-app/c:/Users/MyWindowsUser/AppData/Local/Programs/cursor/resources/app/out/vs/workbench/workbench.desktop.main.js:48:2398)
    at ve.fire (vscode-file://vscode-app/c:/Users/MyWindowsUser/AppData/Local/Programs/cursor/resources/app/out/vs/workbench/workbench.desktop.main.js:48:2617)
    at Git.fire (vscode-file://vscode-app/c:/Users/MyWindowsUser/AppData/Local/Programs/cursor/resources/app/out/vs/workbench/workbench.desktop.main.js:4744:10379)
    at u.onmessage (vscode-file://vscode-app/c:/Users/MyWindowsUser/AppData/Local/Programs/cursor/resources/app/out/vs/workbench/workbench.desktop.main.js:6968:12271)

---

And here is my cursor version information for reference:

Version: 1.2.4 (user setup)
VSCode Version: 1.99.3
Commit: a8e95743c5268be73767c46944a71f4465d05c90
Date: 2025-07-10T17:09:01.383Z
Electron: 34.5.1
Chromium: 132.0.6834.210
Node.js: 20.19.0
V8: 13.2.152.41-electron.0
OS: Windows_NT x64 10.0.26100

[leoing]

+1 Sonnet 4 “model provider ..” error last 24h.