[FEATURE] Multilingual chat title support - stop defaulting to English titles

Preflight Checklist

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

Problem Statement

When a new chat session is started in Claude Code, the conversation title is always generated in English, regardless of the language used by the user. This is inconvenient for non-English speakers, as they have to manually rename every chat to something meaningful in their own language.

For example, if a user starts a conversation in Japanese, the auto-generated title still appears in English (e.g., "How to sort arrays in Python") instead of the user's language (e.g., "Pythonで配列をソートする方法").

Proposed Solution:
Please make the auto-generated chat title multilingual — ideally, the title should be generated in the same language as the user's input. This would greatly improve the experience for non-English users and make Claude Code more accessible globally.

Proposed Solution

When generating the auto-title for a new chat session, detect the language of the user's first message and generate the title in that same language. Alternatively, provide a configuration option that lets users specify their preferred language for chat titles.

Alternative Solutions

Currently, non-English users have to manually rename each chat session title after it is created. This is a workaround but adds friction to the workflow.

Priority

Critical - Blocking my work

Feature Category

CLI commands and flags

Use Case Example

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Additional Context

_No response_