Tools

Lingo.dev's official CLI: lingo push sends JSON, YAML, Markdown, PO, XLIFF, Android/Xcode strings and other files from your repo to its LLM localization engine, and lingo pull brings translations back; CI-ready. Needs a Lingo.dev account; usage-based pricing with a free sandbox.

Agent skills maintained by the Flutter team: layered architecture, responsive layouts, fixing layout overflows, declarative routing, internationalization, JSON serialization, and widget and integration tests. Works alongside the Dart MCP server.

Helps app marketers and translators plan multilingual App Store listings: prioritize countries, research keywords per market, rewrite title, subtitle, keywords and description, and flag screenshot and cultural issues rather than translating literally. Guidance only, no account needed.

AI localization: deploy the server to your own Vercel account (Postgres and AI Gateway included; enable deployment protection afterwards), then run npx languine@selfhosted translate to translate locale files with LLMs. A GitHub Action can open PRs. Needs a Vercel account and Node.js.

Community App Store localization skill (not from Apple): uses the asc CLI and an LLM to translate listing copy such as description, keywords, subtitle and release notes into many languages and sync it to App Store Connect. Needs asc set up and authorized; proofread before submitting.

Unbabel's machine-translation quality metric: comet-score rates translations per sentence and overall, XCOMET marks error spans and severity, and CometKiwi works without a reference. Good for spot-checking MT. Needs Python 3.8+; models download from Hugging Face, some need a license; GPU helps.

Offline translation sync for coding agents: hands only new strings in JSON, YAML, PO, CSV and other locale files to the agent for translation and never overwrites human-edited translations, saving tokens. Needs Node.js; calls no translation API itself.

Crowdin's official CLI: push source files and pull translations back in place, track progress, manage glossaries and TM, and run machine or AI pre-translation, with JSON output for agents. Needs a Crowdin account (free trial; free for open source) and a token; crowdin init sets up config.

Lokalise's official CLI (lokalise2) covering the Lokalise API v2: upload and download language files and manage keys, translations, screenshots, translation tasks and contributors. Needs a Lokalise account (paid, 14-day free trial) and an API token passed via --token.

SimpleLocalize's official CLI: upload and download translation files, trigger machine and AI auto-translation, publish translations to the CDN, and extract translation keys from source code for CI. Needs a SimpleLocalize account and project API key; paid service with a 14-day free trial.

Locize's official CLI: sync local translation files with the Locize platform, add, remove and look up keys, download published translations, manage versions and branches, and export JSON, XLIFF, PO, CSV or Excel for translators. Needs a Locize account, project ID and API key; free plan available.

Phrase Strings' official CLI: phrase init walks you through config, then phrase push uploads language files and phrase pull fetches the latest translations; it also wraps the full API for projects, locales and keys. Needs a Phrase Strings account (paid, 14-day free trial) and an API token.

Crowdin's official plugin with the Crowdin MCP: manage projects and translations in Claude Code, Cowork or Codex, with skills to build glossaries, add translator context, draft translations for review and answer how-tos. Needs a Crowdin account; drafts and glossary uploads need its CLI.