Claude Code responds in English when user speaks Spanish

Description

Claude Code frequently responds in English even when the user is consistently writing in Spanish. This appears to be a regression — previously, Claude Code handled this better and would maintain the conversation language.

Steps to Reproduce

1. Open Claude Code CLI
2. Write prompts and instructions entirely in Spanish
3. Observe that Claude often replies in English instead of Spanish

Expected Behavior

Claude Code should respond in the same language the user is using. If the user writes in Spanish, responses should be in Spanish.

Actual Behavior

Claude Code intermittently switches to English responses despite the user consistently writing in Spanish throughout the conversation.

Environment

• Claude Code CLI (latest version)
• Windows
• Language: Spanish (es)

Additional Context

This worked more consistently in earlier versions. The issue is intermittent — sometimes Claude responds in Spanish correctly, other times it defaults to English without any trigger.