[BUG]

[jarildson]

Describe the bug
During the running of the Strix app, I eventually get this error: X LLM Request Failed
Details: litellm. BadRequestError: AnthropicException
{"type":"error","error":{"type": "invalid_request_error", "message":"This model does not support assistant message prefill. The
conversation must end with a user message."},

To Reproduce
Steps to reproduce the behavior:

1. Use Anthropic provider
2. Use Sonnet 4.6
3. Run against a large python app

Expected behavior
For that error to not happen.

Screenshots
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System Information:

• OS: Ubuntu 22.04
• Strix Version or Commit: Latest -- I think 🐳 Pulling Docker image: ghcr.io/usestrix/strix-sandbox:0.1.10
• Python Version: 3.12
• LLM Used: Claude Sonnet 4.6

Additional context
Add any other context about the problem here.