UI language localization support

[HolliOnRoad]

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

It would be great to have the Claude Code UI (menus, prompts, dialog text) localized into multiple languages.
Currently, /config allows setting the response language, but the interface itself remains in English. Supporting
languages like German, French, Spanish, etc. would make the tool more accessible for non-English speakers.

Proposed Solution

Es wäre toll, wenn die Claude Code-Benutzeroberfläche (Menüs, Eingabeaufforderungen, Dialogtext) in mehreren Sprachen lokalisiert wäre. Derzeit erlaubt /config die Einstellung der Antwortsprache, aber die Schnittstelle selbst bleibt auf Englisch. Unterstützend Sprachen wie Deutsch, Französisch, Spanisch usw. würden das Tool für Nicht-Englischsprachige zugänglicher machen.

Alternative Solutions

No response

Priority

High - Significant impact on productivity

Feature Category

Configuration and settings

Use Case Example

No response

Additional Context

No response

[antomy-gc]

It would be great to support something like localization plugins to allow the community to localize the interface without requiring the Claude team's effort for each new language

[scala-kubotay]

+1 from a Japanese user.

The language setting currently only controls Claude's response language (per schema: "Preferred language for Claude responses and voice dictation"). Interactive UI — slash command dialogs like /hooks, /plugin, /help, confirmation prompts, error messages — remains English-only.

Setting language: japanese makes Claude respond in Japanese, but all menu/dialog UIs are still English, creating an inconsistent surface between the conversation (Japanese) and the CLI (English).

Consider a separate uiLanguage setting so users can mix configurations (e.g., English UI + Japanese responses, or fully Japanese).