i18n Parity
This repository is localized on five independent surfaces, each with its own
mechanism. A change that lands on one and not the others leaves the product
half-translated: the English falls through, and the gap is invisible to anyone
working in English. This skill states the invariant, maps every surface to the
exact files, and gives one command that proves parity.
The invariant: English is the source of truth on every surface, and no change
is done until every supported language carries it in the same PR. A fallback
to English is a safety net, never a completed translation.
Supported languages are declared in one place — supportedLngs in
client/src/i18n/index.ts. Today:
en, zh, vi, ko, es. Everything below derives from that list; the
audit script reads it rather than hard-coding.
The five surfaces
| # |
Surface |
English source of truth |
Translations live in |
Automated gate |
| 1 |
Dashboard UI |
client/src/i18n/locales/en/*.json |
client/src/i18n/locales/<xx>/*.json (same 15 namespaces) |
client/src/i18n/__tests__/i18n.test.ts — key, type, and interpolation-token parity |
| 2 |
Wiki page |
English text in the wiki/index.html DOM |
wiki/script.js (T, ATTRIBUTE_TRANSLATIONS, META, languageLabels, the two language ladders) + wiki/i18n-content.js (window.__WIKI_CONTENT_I18N, both the body bundles and plain) |
client/tests/wiki-i18n.test.ts — live-DOM prose coverage, inline-tag preservation, block-length budgets, asset-version sync |
| 3 |
Mirrored READMEs |
README.md |
README-CN.md (zh), README-VN.md (vi), README-KO.md (ko), README-ES.md (es) |
partial — scripts/i18n-audit.sh (existence, heading count, cross-links) and server/__tests__/plugins-marketplace.test.js (documented counts); prose parity is review-only |
| 4 |
Language switchers |
— |
client/src/components/Sidebar.tsx, client/src/lib/paletteCommands.ts, the two .lang-select-menu blocks in wiki/index.html, nav.json languageNames / languageShort |
scripts/i18n-audit.sh |
| 5 |
Locale-aware formatting |
— |
client/src/lib/format.ts (SupportedLanguage union, getCurrentLanguage() whitelist, getCurrentLocale() BCP-47 map) |
client/src/lib/__tests__/format.test.ts |
What is deliberately NOT localized
Verified against the tree — do not go looking for translation hooks in these,
and do not add them without being asked:
- The root landing page
index.html has no i18n layer. Do not add
data-lang markup; put localized long-form content in the wiki instead. Its
one language-aware element is the Languages (en/zh/…) stat label, which just
enumerates the codes.
client/index.html is an English shell: <html lang="en">,
og:locale=en_US, and English <title>/meta. The React app never reassigns
document.documentElement.lang when the user switches language — a known gap,
not something a translation PR is expected to fix.- The CLI (
bin/ccam.js), the MCP server (mcp/), the Express server
(server/), the desktop shell (desktop/), the VS Code extension, and the
statusline contain no i18n wiring at all. Their output is English.
client/src/lib/event-summary.ts and event-grouping.ts build tool-event
headlines and bullets from English template literals (Last message: …,
3 lines stdout, 2 matches). Their MODULE_GUIDE boilerplate claims strings
belong in i18n JSON, but neither file imports i18next. They sit outside the
key system today; do not "fix" them as part of a localization change.- Number and date formatting is only locale-aware where the
format.ts
helpers are used. Most components call toLocaleString() /
toLocaleString(undefined, …) directly, which follows the browser locale
rather than the chosen UI language. In new code prefer getCurrentLocale()
from format.ts; leave existing call sites alone unless asked.
Workflow A — you changed content (the common case)
Find what you touched in the left column and ship everything in the right column
in the same PR.
| You changed |
You must also do |
| Added/renamed a UI string or i18n key |
Add the key to en and every other locale in the same namespace file. Same key path, same value type, same {{interpolation}} tokens. |
Added a new namespace (new *.json) |
Create it for every locale, then register the imports, the resources entry per language, and the ns array in client/src/i18n/index.ts. |
Added user-visible wiki text in wiki/index.html |
Follow .claude/rules/wiki-i18n.md: scannable layer (the PLAIN selector set — .logo-sub, .section-label, .nav-section, .nav-empty, .stat-label, .t-label, h2/h3/h4, th, .hero-desc, plus .nav-link / .hero-badge trailing text nodes) → T in wiki/script.js; body prose (the HTML_SEL set — p, li, td, th, captions, .callout-body > strong, .route-desc, footer) → wiki/i18n-content.js keyed by whitespace-normalized innerHTML; new alt/aria-label/title/placeholder → ATTRIBUTE_TRANSLATIONS. Then bump CACHE_NAME in wiki/sw.js and the matching ?v= query strings. |
Edited a section of README.md |
Mirror the same edit at the corresponding section of README-CN.md, README-VN.md, README-KO.md, and README-ES.md. All four, every time. |
| Changed behavior that the README/wiki document (env var, event type, route, CLI command, feature) |
Run the update-project-docs skill — it owns the change→docs mapping — then come back here for the translation propagation it triggers. |
| Changed a documented count (plugins, skills, namespaces, languages) |
The count is repeated across all five READMEs, ARCHITECTURE.md, docs/*.md, index.html, wiki/index.html, wiki/i18n-content.js, and asserted in server/__tests__/plugins-marketplace.test.js. Grep the old number repo-wide; update every hit. |
Workflow B — adding a new language
This is a large, exact, mechanical change. Read
references/new-language-checklist.md
and work through it top to bottom — it lists every file, in dependency order,
with the exact edit for each.
The three things contributors most often ship incomplete, stated up front:
- The README mirror must be complete.
README-<XX>.md is a full mirror of
README.md — every section, every table row, every code block, every mermaid
diagram, in the same order. Do not summarize, do not drop "less important"
sections, do not stop halfway. Diff the heading list against README.md
before you open the PR — the audit script compares heading counts, which
catches a truncated mirror but not a reordered or silently condensed one.
- Every app key must be translated. All 15 namespaces × every key. The
parity test fails on a missing key, but it passes on a key you copied over
in English — so read your diff for untranslated leftovers.
- The wiki must be translated completely, not just the headings. That means
a full
<xx> bundle in wiki/i18n-content.js (thousands of body strings), a
full <xx> block in T, META, and every entry of ATTRIBUTE_TRANSLATIONS
in wiki/script.js. A locale that only fills T renders a page with
translated headings over English paragraphs, which is worse than English.
What stays in English (all surfaces)
Never translate: code inside <code>/backticks, commands, file and directory
paths, URLs, env-var names, HTTP methods and status codes, CLI flags, code
identifiers, numbers with units, brand and product names (Claude Code, MCP,
Codex), Claude Code hook event names (PreToolUse, Stop, …), and Claude
Code tool names (Bash, Agent, Read, Edit). Translate only the prose
around them. A block that is entirely code or identifiers needs no wiki
entry — it correctly falls back to English.
Two different things are spelled Agent. The Claude Code tool named
Agent (alongside Bash, Read, Edit) is an identifier and stays literal in
every locale, everywhere it appears — hook-event tables, tool lists, event
names. The UI noun for an agent (common:agent / common:subagent) is
product vocabulary with a per-locale contract, and only that noun has the
Spanish exception below. Never carry the exception into the tool name.
The UI noun's contract, asserted by client/src/i18n/__tests__/i18n.test.ts:
zh, vi, and ko keep Agent / Subagent literal; es renders them
agente / subagente. A new locale must decide this explicitly and add its
row to that test.
Terminology, per-locale conventions, and the shared glossary live in
references/translation-style.md. Read it
before translating; drifting terminology across pages is the most common
review comment on localization PRs.
Two traps worth knowing before you edit the wiki
client/tests/wiki-i18n.test.ts parses wiki/script.js by exact source
markers. It slices the file between literal strings — " const T = " …
"\n\n const PLAIN", " const ATTRIBUTE_TRANSLATIONS = " …
"\n const ATTR", " const META = " … "\n const trH" — and evals
what it finds. Renaming, reordering, or re-indenting those declarations
breaks the test with a confusing error. Add locales inside the existing
objects; leave the declaration lines alone.- The wiki's chosen language lives in
localStorage["wiki-lang"], not a URL
parameter. There is no ?lang= support. First visit falls back to a
navigator.language prefix ladder in wiki/script.js. To preview a locale,
use the switcher, or run
localStorage.setItem("wiki-lang", "<xx>") in the console and reload.
This skill is mirrored for every agent
The canonical copy — and both scripts — live at .claude/skills/i18n-parity/.
It is mirrored, with links rewritten to repo-root-relative paths and an
agents/openai.yaml interface added, to:
.agents/skills/i18n-parity/ (the shared/OpenAI skill tree).codex/skills/i18n-parity/ (Codex)
Editing this skill means regenerating the mirrors — edit the canonical copy,
then run:
bash .claude/skills/i18n-parity/scripts/sync-agent-mirrors.sh
i18n-audit.sh runs that script in --check mode, so a stale mirror is a
reported gap rather than silent drift. The mirrors carry no scripts: they point
back at the canonical ones by repo-root path.
Verify (do not skip)
# 1. Cross-surface parity: locale sets, namespace files, key parity, switcher
# entries, wiki bundles, README mirrors and cross-links, agent-skill mirrors.
bash .claude/skills/i18n-parity/scripts/i18n-audit.sh
# 2. UI key/type/interpolation parity + locale formatting
npm run test:client
# 3. Wiki live-DOM coverage, inline tags, metadata, cache versions
cd client && npx vitest run tests/wiki-i18n.test.ts && cd ..
# 4. Documented counts asserted against the source tree
npm run test:server
# 5. The static wiki files and locale JSON are Prettier-managed
npm run format
i18n-audit.sh exits non-zero and names the exact file and locale for every
gap. Every check is a structural one — a named thing is present or it is not —
with a single exception: the wiki/i18n-content.js bundle-size check is a
stub detector (it flags a locale holding under 60% of the largest bundle's
entries). Exact per-string wiki coverage is asserted by
client/tests/wiki-i18n.test.ts, which walks the live DOM.
State explicitly which surfaces you updated and which you intentionally skipped
(with the reason), per the repo's verification policy in CLAUDE.md.
Tips
- Write the English first and get it right, on all surfaces, before
translating anything. Every other locale is derived from it; re-translating
because the English moved is the biggest waste in this workflow.
- To find where a string already lives:
grep -rn "<neighbouring English text>" client/src/i18n/locales/en wiki/i18n-content.js wiki/script.js.
- When adding a language, one locale per subagent is fine for the wiki body
bundle (it is large), but keep the README mirror with a single author so the
section order and terminology stay coherent.
- Wiki edits are cache-first: forgetting the
CACHE_NAME / ?v= bump means
returning visitors never see the translation you just shipped.
1---2name: i18n-parity3description: MANDATORY for every coding agent and contributor touching localized content — keep all five localization surfaces (dashboard UI keys, wiki page, mirrored READMEs, locale-aware formatting, language switchers) in parity across every supported language. Use automatically (without being asked) whenever you add or change user-visible UI copy, add an i18n key, edit README.md, edit wiki/index.html, or change docs that the READMEs and wiki mirror — and use the full new-language checklist whenever adding a language (a new README-XX.md, a new client/src/i18n/locales/<xx>/ directory, or a new lang-option in the wiki).4---56# i18n Parity78This repository is localized on **five independent surfaces**, each with its own9mechanism. A change that lands on one and not the others leaves the product10half-translated: the English falls through, and the gap is invisible to anyone11working in English. This skill states the invariant, maps every surface to the12exact files, and gives one command that proves parity.1314**The invariant: English is the source of truth on every surface, and no change15is done until every supported language carries it in the same PR.** A fallback16to English is a safety net, never a completed translation.1718Supported languages are declared in one place — `supportedLngs` in19[`client/src/i18n/index.ts`](../../../client/src/i18n/index.ts). Today:20**`en`, `zh`, `vi`, `ko`, `es`**. Everything below derives from that list; the21audit script reads it rather than hard-coding.2223## The five surfaces2425| # | Surface | English source of truth | Translations live in | Automated gate |26|---|---|---|---|---|27| 1 | **Dashboard UI** | `client/src/i18n/locales/en/*.json` | `client/src/i18n/locales/<xx>/*.json` (same 15 namespaces) | `client/src/i18n/__tests__/i18n.test.ts` — key, type, and interpolation-token parity |28| 2 | **Wiki page** | English text in the `wiki/index.html` DOM | `wiki/script.js` (`T`, `ATTRIBUTE_TRANSLATIONS`, `META`, `languageLabels`, the two language ladders) + `wiki/i18n-content.js` (`window.__WIKI_CONTENT_I18N`, both the body bundles and `plain`) | `client/tests/wiki-i18n.test.ts` — live-DOM prose coverage, inline-tag preservation, block-length budgets, asset-version sync |29| 3 | **Mirrored READMEs** | `README.md` | `README-CN.md` (zh), `README-VN.md` (vi), `README-KO.md` (ko), `README-ES.md` (es) | partial — `scripts/i18n-audit.sh` (existence, heading count, cross-links) and `server/__tests__/plugins-marketplace.test.js` (documented counts); prose parity is review-only |30| 4 | **Language switchers** | — | `client/src/components/Sidebar.tsx`, `client/src/lib/paletteCommands.ts`, the two `.lang-select-menu` blocks in `wiki/index.html`, `nav.json` `languageNames` / `languageShort` | `scripts/i18n-audit.sh` |31| 5 | **Locale-aware formatting** | — | `client/src/lib/format.ts` (`SupportedLanguage` union, `getCurrentLanguage()` whitelist, `getCurrentLocale()` BCP-47 map) | `client/src/lib/__tests__/format.test.ts` |3233### What is deliberately NOT localized3435Verified against the tree — do not go looking for translation hooks in these,36and do not add them without being asked:3738- **The root landing page `index.html`** has no i18n layer. Do not add39 `data-lang` markup; put localized long-form content in the wiki instead. Its40 one language-aware element is the `Languages (en/zh/…)` stat label, which just41 enumerates the codes.42- **`client/index.html`** is an English shell: `<html lang="en">`,43 `og:locale=en_US`, and English `<title>`/meta. The React app never reassigns44 `document.documentElement.lang` when the user switches language — a known gap,45 not something a translation PR is expected to fix.46- **The CLI (`bin/ccam.js`), the MCP server (`mcp/`), the Express server47 (`server/`), the desktop shell (`desktop/`), the VS Code extension, and the48 statusline** contain no i18n wiring at all. Their output is English.49- **`client/src/lib/event-summary.ts` and `event-grouping.ts`** build tool-event50 headlines and bullets from English template literals (`Last message: …`,51 `3 lines stdout`, `2 matches`). Their MODULE_GUIDE boilerplate claims strings52 belong in i18n JSON, but neither file imports i18next. They sit outside the53 key system today; do not "fix" them as part of a localization change.54- **Number and date formatting is only locale-aware where the `format.ts`55 helpers are used.** Most components call `toLocaleString()` / 56 `toLocaleString(undefined, …)` directly, which follows the *browser* locale57 rather than the chosen UI language. In new code prefer `getCurrentLocale()`58 from `format.ts`; leave existing call sites alone unless asked.5960## Workflow A — you changed content (the common case)6162Find what you touched in the left column and ship everything in the right column63**in the same PR**.6465| You changed | You must also do |66|---|---|67| Added/renamed a UI string or i18n key | Add the key to `en` **and every other locale** in the same namespace file. Same key path, same value type, same `{{interpolation}}` tokens. |68| Added a new namespace (new `*.json`) | Create it for every locale, then register the imports, the `resources` entry per language, and the `ns` array in `client/src/i18n/index.ts`. |69| Added user-visible wiki text in `wiki/index.html` | Follow [`.claude/rules/wiki-i18n.md`](../../rules/wiki-i18n.md): scannable layer (the `PLAIN` selector set — `.logo-sub`, `.section-label`, `.nav-section`, `.nav-empty`, `.stat-label`, `.t-label`, `h2`/`h3`/`h4`, `th`, `.hero-desc`, plus `.nav-link` / `.hero-badge` trailing text nodes) → `T` in `wiki/script.js`; body prose (the `HTML_SEL` set — `p`, `li`, `td`, `th`, captions, `.callout-body > strong`, `.route-desc`, footer) → `wiki/i18n-content.js` keyed by whitespace-normalized `innerHTML`; new `alt`/`aria-label`/`title`/`placeholder` → `ATTRIBUTE_TRANSLATIONS`. Then bump `CACHE_NAME` in `wiki/sw.js` and the matching `?v=` query strings. |70| Edited a section of `README.md` | Mirror the **same** edit at the corresponding section of `README-CN.md`, `README-VN.md`, `README-KO.md`, and `README-ES.md`. All four, every time. |71| Changed behavior that the README/wiki document (env var, event type, route, CLI command, feature) | Run the [`update-project-docs`](../update-project-docs/SKILL.md) skill — it owns the change→docs mapping — then come back here for the translation propagation it triggers. |72| Changed a documented count (plugins, skills, namespaces, languages) | The count is repeated across all five READMEs, `ARCHITECTURE.md`, `docs/*.md`, `index.html`, `wiki/index.html`, `wiki/i18n-content.js`, and asserted in `server/__tests__/plugins-marketplace.test.js`. Grep the old number repo-wide; update every hit. |7374## Workflow B — adding a new language7576This is a large, exact, mechanical change. **Read77[`references/new-language-checklist.md`](references/new-language-checklist.md)78and work through it top to bottom** — it lists every file, in dependency order,79with the exact edit for each.8081The three things contributors most often ship incomplete, stated up front:82831. **The README mirror must be complete.** `README-<XX>.md` is a full mirror of84 `README.md` — every section, every table row, every code block, every mermaid85 diagram, in the same order. Do not summarize, do not drop "less important"86 sections, do not stop halfway. Diff the heading list against `README.md`87 before you open the PR — the audit script compares heading counts, which88 catches a truncated mirror but not a reordered or silently condensed one.892. **Every app key must be translated.** All 15 namespaces × every key. The90 parity test fails on a missing key, but it *passes* on a key you copied over91 in English — so read your diff for untranslated leftovers.923. **The wiki must be translated completely**, not just the headings. That means93 a full `<xx>` bundle in `wiki/i18n-content.js` (thousands of body strings), a94 full `<xx>` block in `T`, `META`, and every entry of `ATTRIBUTE_TRANSLATIONS`95 in `wiki/script.js`. A locale that only fills `T` renders a page with96 translated headings over English paragraphs, which is worse than English.9798## What stays in English (all surfaces)99100Never translate: code inside `<code>`/backticks, commands, file and directory101paths, URLs, env-var names, HTTP methods and status codes, CLI flags, code102identifiers, numbers with units, brand and product names (`Claude Code`, `MCP`,103`Codex`), Claude Code hook event names (`PreToolUse`, `Stop`, …), and Claude104Code tool names (`Bash`, `Agent`, `Read`, `Edit`). Translate only the prose105around them. A block that is *entirely* code or identifiers needs no wiki106entry — it correctly falls back to English.107108**Two different things are spelled `Agent`.** The Claude Code **tool** named109`Agent` (alongside `Bash`, `Read`, `Edit`) is an identifier and stays literal in110**every** locale, everywhere it appears — hook-event tables, tool lists, event111names. The **UI noun** for an agent (`common:agent` / `common:subagent`) is112product vocabulary with a per-locale contract, and only that noun has the113Spanish exception below. Never carry the exception into the tool name.114115The UI noun's contract, asserted by `client/src/i18n/__tests__/i18n.test.ts`:116`zh`, `vi`, and `ko` keep `Agent` / `Subagent` literal; `es` renders them117`agente` / `subagente`. A new locale must decide this explicitly and add its118row to that test.119120Terminology, per-locale conventions, and the shared glossary live in121[`references/translation-style.md`](references/translation-style.md). Read it122before translating; drifting terminology across pages is the most common123review comment on localization PRs.124125## Two traps worth knowing before you edit the wiki1261271. **`client/tests/wiki-i18n.test.ts` parses `wiki/script.js` by exact source128 markers.** It slices the file between literal strings — `" const T = "` …129 `"\n\n const PLAIN"`, `" const ATTRIBUTE_TRANSLATIONS = "` …130 `"\n const ATTR"`, `" const META = "` … `"\n const trH"` — and `eval`s131 what it finds. Renaming, reordering, or re-indenting those declarations132 breaks the test with a confusing error. Add locales *inside* the existing133 objects; leave the declaration lines alone.1342. **The wiki's chosen language lives in `localStorage["wiki-lang"]`, not a URL135 parameter.** There is no `?lang=` support. First visit falls back to a136 `navigator.language` prefix ladder in `wiki/script.js`. To preview a locale,137 use the switcher, or run138 `localStorage.setItem("wiki-lang", "<xx>")` in the console and reload.139140## This skill is mirrored for every agent141142The canonical copy — and both scripts — live at `.claude/skills/i18n-parity/`.143It is mirrored, with links rewritten to repo-root-relative paths and an144`agents/openai.yaml` interface added, to:145146- `.agents/skills/i18n-parity/` (the shared/OpenAI skill tree)147- `.codex/skills/i18n-parity/` (Codex)148149**Editing this skill means regenerating the mirrors** — edit the canonical copy,150then run:151152```bash153bash .claude/skills/i18n-parity/scripts/sync-agent-mirrors.sh154```155156`i18n-audit.sh` runs that script in `--check` mode, so a stale mirror is a157reported gap rather than silent drift. The mirrors carry no scripts: they point158back at the canonical ones by repo-root path.159160## Verify (do not skip)161162```bash163# 1. Cross-surface parity: locale sets, namespace files, key parity, switcher164# entries, wiki bundles, README mirrors and cross-links, agent-skill mirrors.165bash .claude/skills/i18n-parity/scripts/i18n-audit.sh166167# 2. UI key/type/interpolation parity + locale formatting168npm run test:client169170# 3. Wiki live-DOM coverage, inline tags, metadata, cache versions171cd client && npx vitest run tests/wiki-i18n.test.ts && cd ..172173# 4. Documented counts asserted against the source tree174npm run test:server175176# 5. The static wiki files and locale JSON are Prettier-managed177npm run format178```179180`i18n-audit.sh` exits non-zero and names the exact file and locale for every181gap. Every check is a structural one — a named thing is present or it is not —182with a single exception: the `wiki/i18n-content.js` bundle-size check is a183**stub detector** (it flags a locale holding under 60% of the largest bundle's184entries). Exact per-string wiki coverage is asserted by185`client/tests/wiki-i18n.test.ts`, which walks the live DOM.186187State explicitly which surfaces you updated and which you intentionally skipped188(with the reason), per the repo's verification policy in `CLAUDE.md`.189190## Tips191192- **Write the English first and get it right**, on all surfaces, before193 translating anything. Every other locale is derived from it; re-translating194 because the English moved is the biggest waste in this workflow.195- To find where a string already lives: `grep -rn "<neighbouring English text>"196 client/src/i18n/locales/en wiki/i18n-content.js wiki/script.js`.197- When adding a language, one locale per subagent is fine for the *wiki body*198 bundle (it is large), but keep the README mirror with a single author so the199 section order and terminology stay coherent.200- Wiki edits are cache-first: forgetting the `CACHE_NAME` / `?v=` bump means201 returning visitors never see the translation you just shipped.
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