[Bug] Intermittent OAuthError on Claude Code session start on macOS

Bug Description
Title: [BUG] Claude Code (Desktop) — Intermittent OAuthError: Unable to start session when starting new session on macOS --- ### Preflight Checklist - [x] I have searched existing issues (related: #47104) - [x] This is a single bug report - [x] I am using the latest version of Claude Code / Claude Desktop ### What's Wrong? When starting a new session in Claude Code (via Claude Desktop) on macOS, the session intermittently fails to start with the following error: `` Something went wrong Try sending your message again. If it keeps happening, share feedback so we can investigate. OAuthError: Unable to start session. Check your internet connection and try again. ` This happens randomly — sometimes a session starts fine, other times it fails with this OAuth error. It is **not** an actual internet connectivity problem: at the same moment the failure occurs, claude.ai in the browser works perfectly normally on the same machine and same network. This appears similar to issue #47104, but in my case it is intermittent rather than caused by a specific auto-update, and only Claude Code is affected (Cowork and Connectors are working). ### What Should Happen? New Claude Code sessions should start reliably without OAuth errors, given that the underlying network and authentication (browser claude.ai) are working correctly. ### Steps to Reproduce 1. Open Claude Desktop on macOS (latest version, fully up to date) 2. Start a new Claude Code session 3. Sometimes it works; other times it fails immediately with the OAuth error above 4. Retrying may or may not work — behavior is random ### Error Messages / Logs ` OAuthError: Unable to start session. Check your internet connection and try again. `` ### Environment - OS: macOS (latest) - App: Claude Desktop (latest, auto-updates enabled) - Claude Code: latest - Plan: Max - Network: working normally — claude.ai in browser works fine at the same moment the error occurs - VPN: none active - Other Claude features affected? No — only Claude Code session start. Browser chat and other Desktop features work. ### Frequency Intermittent / random. Not tied to a specific update or trigger that I can identify. Some session starts succeed, others fail with this error on the same machine, same network, within minutes of each other. ### Is this a regression? Unclear — has been happening over multiple Claude Desktop versions. ### Additional Information - Browser (claude.ai) authentication works fine simultaneously, which strongly suggests this is not a network or general OAuth issue but specifically a session-initialization problem in the Desktop OAuth flow for Claude Code. - Restarting Claude Desktop sometimes (but not always) resolves it temporarily. - The error message is misleading since internet connectivity is verifiably fine.

Environment Info

• Platform: darwin
• Terminal: Apple_Terminal
• Version: 2.1.138
• Feedback ID: b8f13bfd-bd01-4c89-8134-5ce88bd8684f

Errors

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