[BUG] Claude Desktop SSO authentication fails with "Invalid authorization" after successful SAML response

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?

Environment:
Claude Desktop Version: latest
Operating System: macOS 26
SSO Provider: Okta (via WorkOS)
Organization Plan: Teams

Bug Description:
Claude Desktop fails to complete SSO authentication with "Invalid authorization" error, despite successful SAML authentication. The same SSO configuration works perfectly on claude.ai web interface.

Technical Details:
SAML authentication succeeds on the IdP side (verified via SAML response inspection)
The SAML RelayState includes: "redirect_uri":"https://claude.ai/sso-callback/desktop-app"
Issue appears to be with how Claude Desktop handles the SSO callback after successful WorkOS authentication
Authentication completes successfully, but desktop app doesn't receive/process the callback

What Should Happen?

Expected Behavior:
Claude Desktop should complete the SSO flow and log the user in, just like claude.ai web interface does.
Actual Behavior:
The app displays "Invalid authorization" error immediately upon opening, before any interaction. The error appears even after successful SAML authentication in the browser.

Error Messages/Logs

Steps to Reproduce

Steps to Reproduce:
Open Claude Desktop app
Attempt to sign in (SSO is enforced for organization)
App redirects to Okta SSO login
Complete authentication successfully in browser
SAML response returns with Success status
Desktop app displays "Invalid authorization" error

Claude Model

None

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

Latest - Claude Desktop

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Warp

Additional Information

Claude Desktop SSO problem