[BUG] Sonnet model returns 404 "model: sonnet" error, Opus works fine

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?

Claude Code consistently returns a 404 error when trying to use the default Sonnet model:
{"type":"not_found_error","message":"model: sonnet"}

Switching to Opus using /model works immediately with no issues.

• Duration: 24+ hours
• Affects: Multiple devices (PC and phone)
• Sample request IDs: req_011CU599UgWFLvJuNcDQJdkU, req_011CU58QTCkrn8uekGm4N3EP
• Subscription: Max

Commands that fail with Sonnet but work with Opus:

• whoami
• Any default Claude Code command

The error suggests a model routing or availability issue on Anthropic's backend.

What Should Happen?

Claude Code consistently returns a 404 error when trying to use the default Sonnet model:
{"type":"not_found_error","message":"model: sonnet"}

Switching to Opus using /model works immediately with no issues.

• Duration: 24+ hours
• Affects: Multiple devices (PC and phone)
• Sample request IDs: req_011CU599UgWFLvJuNcDQJdkU, req_011CU58QTCkrn8uekGm4N3EP
• Subscription: Max

Commands that fail with Sonnet but work with Opus:

• whoami
• Any default Claude Code command

The error suggests a model routing or availability issue on Anthropic's backend.

Error Messages/Logs

Steps to Reproduce

Claude Code consistently returns a 404 error when trying to use the default Sonnet model:
{"type":"not_found_error","message":"model: sonnet"}

Switching to Opus using /model works immediately with no issues.

• Duration: 24+ hours
• Affects: Multiple devices (PC and phone)
• Sample request IDs: req_011CU599UgWFLvJuNcDQJdkU, req_011CU58QTCkrn8uekGm4N3EP
• Subscription: Max

Commands that fail with Sonnet but work with Opus:

• whoami
• Any default Claude Code command

The error suggests a model routing or availability issue on Anthropic's backend.

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

1.0.120

Platform

Other

Operating System

Other Linux

Terminal/Shell

Other

Additional Information

Going on nearly 24 hours now