claude-code - 💡(How to fix) Fix [FEATURE] Feature request: Make sidebar conversation title language match user's input language

Preflight Checklist

• I have searched existing requests and this feature hasn't been requested yet
• This is a single feature request (not multiple features)

Problem Statement

Problem

The auto-generated titles in the sidebar are often in English even when the entire conversation is conducted in Japanese. This makes it harder to scan and identify past sessions for non-English users.

Example

• My conversations are 95%+ in Japanese
• First user message is pure Japanese (e.g., "前セッションからの引き継ぎ...")
• Yet some titles come out in English (likely because the content contains technical terms like filenames, "Phase 6", etc.)
• Inconsistency: some sessions get Japanese titles, others get English titles for similar content

Proposed Solution

Proposed solution

Either of:

1. A setting in ~/.claude/settings.json to specify preferred title language (e.g., "titleLanguage": "ja" or "auto")
2. Default behavior: match the dominant language of the conversation
3. Allow manual rename of session titles from the sidebar

Environment

• Claude Code version: 2.1.114
• Platform: macOS (VSCode extension / native app)
• Language: Japanese

Additional context

Even when explicitly starting a new session with Japanese text, the title often renders in English, suggesting the summarizer model's system prompt biases toward English output regardless of input language.

Alternative Solutions

No response

Priority

Critical - Blocking my work

Feature Category

CLI commands and flags

Use Case Example

No response

Additional Context

No response