[BUG] All API requests return 500 Internal Server Error — including /logout — while claude.ai works fine (Claude Max, Opus 4.5, v2.1.29)

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

Every API request from Claude Code returns HTTP 500, including basic prompts and even the logout command. This is happening simultaneously in both a standalone macOS Terminal and a Cursor IDE terminal, ruling out any IDE-specific cause. Meanwhile, claude.ai with Opus 4.5 works perfectly in the browser — same account, same machine, same network.

What I've tested:

• Simplest possible prompt ("Are you alive? Answer yes or no") → 500
• Fresh terminal session outside any project directory (/Users/jakehill) → 500
• Cursor IDE terminal inside project directory (~/Documents/Git/perry-video-editor) → 500
• claude logout command in Mac Terminal → 500
• claude logout command in Cursor terminal → 500
• claude.ai web interface with Opus 4.5 → Works perfectly

Request IDs (all returned 500):

• req_011CXmPybEgY8UvmSU8Eyf5f — prompt in Cursor terminal
• req_011CXmQ2vfp6EDPNG95cWif6 — prompt in Mac Terminal
• req_011CXmQM3ue2MkhjXGw8boqg — logout in Mac Terminal
• req_011CXmQPFxUxGNyxovk1bdfP — logout in Cursor terminal

The fact that even logout returns 500 confirms this is a server-side issue affecting all Claude Code API requests for this account, not a prompt/context/session problem.

What Should Happen?

Claude Code should respond to prompts and execute commands (including logout) without 500 errors, consistent with the behavior of claude.ai on the same account.

• Platform: darwin (macOS, Apple Silicon)
• Terminal: Mac Terminal.app AND Cursor IDE terminal (both fail identically)
• Version: 2.1.29
• Account: Claude Max subscription, Opus 4.5
• Auth: OAuth (jakeh134@gmail.com's Organization)

Error Messages/Logs

[{"error":"Error: 500 {\"type\":\"error\",\"error\":{\"type\":\"api_error\",\"message\":\"Internal server error\"},\"request_id\":\"req_011CXmPybEgY8UvmSU8Eyf5f\"}"},{"error":"Error: 500 {\"type\":\"error\",\"error\":{\"type\":\"api_error\",\"message\":\"Internal server error\"},\"request_id\":\"req_011CXmQ2vfp6EDPNG95cWif6\"}"},{"error":"Error: 500 {\"type\":\"error\",\"error\":{\"type\":\"api_error\",\"message\":\"Internal server error\"},\"request_id\":\"req_011CXmQM3ue2MkhjXGw8boqg\"}"},{"error":"Error: 500 {\"type\":\"error\",\"error\":{\"type\":\"api_error\",\"message\":\"Internal server error\"},\"request_id\":\"req_011CXmQPFxUxGNyxovk1bdfP\"}"}]

Steps to Reproduce

1. Open macOS Terminal (not inside any IDE)
2. Run claude from home directory (/Users/jakehill)
3. Trust the workspace when prompted
4. Type any prompt (e.g., "Are you alive? Answer yes or no")
5. Observe: API Error 500
6. Type logout
7. Observe: API Error 500 again
8. Open Cursor IDE terminal, navigate to any project directory
9. Run claude
10. Repeat steps 4-7 — identical 500 errors
11. Open claude.ai in browser, select Opus 4.5, send same prompt
12. Observe: Works perfectly

No files, code, or special context needed to reproduce. The simplest possible prompt fails.

Claude Model

Not sure / Multiple models

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

2.1.29

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

<img width="580" height="397" alt="Image" src="https://github.com/user-attachments/assets/0ed00364-595d-4ad3-98e1-bcf547dcf6a7" />
<img width="578" height="386" alt="Image" src="https://github.com/user-attachments/assets/59f76533-c526-4ddb-8ca7-dd28bd00c18f" />
<img width="517" height="109" alt="Image" src="https://github.com/user-attachments/assets/53722cc4-198c-4919-9dc8-9c1ac7333cab" />
<img width="1222" height="246" alt="Image" src="https://github.com/user-attachments/assets/c32025ad-8cd1-4f3f-aea7-f2b6e1db31bd" />
<img width="1208" height="829" alt="Image" src="https://github.com/user-attachments/assets/509efdb0-9dcd-40bd-8700-3d8c7070e87c" />

Key Evidence: Server-side, not client-side

• claude.ai works perfectly with Opus 4.5 on the same account, machine, and network at the exact same time Claude Code fails
• Even claude logout returns 500 — this command just revokes an OAuth token and requires no prompt processing, context, or model inference. If logout 500s, the entire Claude Code API path is broken.
• Two completely independent terminals fail identically — macOS Terminal.app from home directory AND Cursor IDE terminal from a project directory
• No CLAUDE.md or project context involved — fails from /Users/jakehill with zero project files loaded
• Status page shows "Operational" for Claude Code at time of filing (Feb 3, 2026, ~9:50 AM CST)

Request IDs for backend tracing

| Request ID | Action | Terminal |
|---|---|---|
| req_011CXmPybEgY8UvmSU8Eyf5f | Simple prompt | Cursor IDE |
| req_011CXmQ2vfp6EDPNG95cWif6 | Simple prompt | Mac Terminal |
| req_011CXmQM3ue2MkhjXGw8boqg | logout command | Mac Terminal |
| req_011CXmQPFxUxGNyxovk1bdfP | logout command | Cursor IDE |

All four returned identical 500 Internal Server Error responses within a ~10 minute window.