Claude Code (Anthropic) / AI Coding Tools

Claude Code API Provider fails with exit code 1 for all Sonnet models

Fix complete model failure in Claude Code where all Anthropic Sonnet models return exit code 1, blocking all AI-assisted coding sessions Includes evidence for Claude Code (Anthropic) troubleshooting demand.

Category
AI Coding Tools
Error signature
Command failed with exit code 1 for all sonnet models via Claude Code API Provider
Quick fix
Compare the failing environment with a known working setup, then change one configuration value at a time.
Updated

What this error means

Command failed with exit code 1 for all sonnet models via Claude Code API Provider is a Claude Code (Anthropic) failure pattern reported for developers trying to fix complete model failure in claude code where all anthropic sonnet models return exit code 1, blocking all ai-assisted coding sessions. Based on the imported evidence, treat this as a tool-specific troubleshooting page rather than a generic API error.

Why this happens

GitHub issue #10135 in cline/cline (opened Apr 4, 2026). All Sonnet models fail with exit code 1 through the Claude Code API Provider. 9 comments indicating persistent issue affecting paying users. Critical error — no Claude models work. Maps to ‘AI Coding Tools’.

Common causes

Quick fixes

  1. Confirm the exact error signature matches Command failed with exit code 1 for all sonnet models via Claude Code API Provider.
  2. Check the Claude Code (Anthropic) account, local tool state, and provider configuration involved in the failing workflow.
  3. Compare the failing environment with a known working setup, then change one configuration value at a time.

Platform/tool-specific checks

Step-by-step troubleshooting

  1. Capture the exact error message and the command, editor action, or request that triggered it.
  2. Check whether the failure is account/auth, quota/rate, model/provider, local runtime, or deployment configuration.
  3. Review the source evidence below and compare it with your environment.
  4. Apply one change at a time and rerun the smallest failing action.
  5. Keep the working fix documented for the team or deployment environment.

How to prevent it

Sources checked

Evidence note: GitHub issue #10135 in cline/cline (opened Apr 4, 2026). All Sonnet models fail with exit code 1 through the Claude Code API Provider. 9 comments indicating persistent issue affecting paying users. Critical error — no Claude models work. Maps to ‘AI Coding Tools’.

FAQ

What should I check first?

Start with the exact Command failed with exit code 1 for all sonnet models via Claude Code API Provider text and the smallest action that reproduces it.

Can I ignore this error?

No. Treat it as a failed Claude Code (Anthropic) workflow until the root cause is understood.

Is this guaranteed to have one fix?

No. The imported evidence supports the troubleshooting path above, but tool behavior can vary by account, plan, version, provider, and local configuration.

How do I know the fix worked?

Rerun the same command, editor action, or request. The fix is working when that action completes without Command failed with exit code 1 for all sonnet models via Claude Code API Provider.