AI: Claude Code fallback to Claude 4 Sonnet is not triggered

[johnnydevriese]

Summary

Claude Agent will not fallback to use Claude Sonnet 4 when out of Claude Opus 4.1 tokens.

Description

Steps to trigger the problem:

1. Use all of your Claude Opus 4.1 tokens
2. Run Zed
3. Try to make a request to Claude 4 sonnet

Expected Behavior:

I would expect Zed Claude Code Agent to fallback to use Claude Sonnet 4.

Actual Behavior:

Zed Claude Code will not allow me to do anything

Claude Code will fallback to using Sonnet

Model Provider Details

• Provider: Anthropic with Teams Account
• Model Name: Claude 4 Sonnet
• Mode: Agent Panel
• Other Details (MCPs, other settings, etc): I found a workaround of explicitly setting export ANTHROPIC_MODEL="claude-sonnet-4-20250514" so it never attempts to use Claude Opus 4.1.

Zed Version and System Specs

Zed: v0.204.5 (Zed)
OS: macOS 26.0
Memory: 36 GiB
Architecture: aarch64