Feature: word-by-word gloss (interlinear translation) under English text, esp. thinking blocks

Summary

For non-native English speakers, add an optional word-by-word gloss (interlinear translation) rendered underneath English text in the UI — especially thinking blocks — in the user's configured language.

Motivation

I use Claude Code in Korean (CLAUDE.md instructs Korean responses), but thinking blocks are always emitted in English and are not language-controllable from the user side. So a large amount of the text I read every day is English I did not ask for.

That turns out to be an opportunity rather than only a problem: those blocks are high-quality, domain-relevant English about my own code, which is close to ideal study material. Today I work around it by instructing Claude to hand-write an interlinear gloss at the top of each reply:

An  event  interrupts  the  rotation  to  prioritize  the  alert.
한  사건이  중단시킨다   그   순환을   위해   우선하다   그   경보를

사건이 발생하면 순환을 멈추고 그 경보를 우선 처리한다.

This works, but it burns model tokens, pushes the actual answer down the screen, depends on the model remembering to do it, and can't be applied to the thinking blocks themselves (they're already streamed by then).

Proposal

A client-side rendering option, e.g. /config → "Gloss English text", with:

• Target language — default to the user's locale / CLAUDE.md language.
• Scope — thinking blocks only (my main need) / all assistant text / off (default).
• Density — every word, or only words above a difficulty threshold (skip the, is, and; gloss interrupts, prioritize, deprecated).
• Interaction — an unobtrusive form such as hover/tap on a word to reveal its meaning, or a toggle that expands the interlinear line beneath the paragraph, so it doesn't wreck the layout when off.

Skipping code spans, file paths, identifiers, and commands is essential — glossing npm run build or a variable name is noise.

Why in the client rather than in the prompt

• Thinking blocks can be glossed at render time; the model can't retroactively annotate its own already-streamed reasoning.
• No token cost and no latency added to the answer.
• Deterministic — it doesn't depend on the model remembering an instruction across a long session.
• It's a display concern, which is where display concerns belong.

Scope note

I'd be happy with a minimal first version: thinking blocks only, hover-to-reveal, one target language from a config key. The value is mostly in it being automatic and always-on for people who read English all day but don't think in it.

Environment

• Claude Code Desktop (Microsoft Store / MSIX) Claude_1.32352.1.0, engine 2.1.229
• Windows 11 Pro 26200
• Working language: Korean