AI 編碼智能體會用你的語言搜尋網頁嗎？Claude Code 和 Codex 的 5 種語言測試
Do AI coding agents search the web in your language? I tested Claude Code and Codex in 5 languages
Claude Code（Opus 5.5）和 Codex CLI 的 320 次網頁搜尋測試發現，全球性 AI 產品話題的 206 次搜尋中，205 次使用英文。地方議題方面，以當地語言提問時，Claude Code 和 Codex 分別有 82% 和 50% 以當地語言搜尋；以英文提問時則為 49% 和 17%。320 個答案全都使用提問語言，因此單看答案通常無法判斷引用來源的語言。
When you ask an AI agent something in Korean or Spanish, does it search in that language? I ran 320 web-search sessions with Claude Code (Opus 5.5) and Codex CLI to find out.
Global topic (AI products), asked in Korean, Japanese, Spanish or Ukrainian:
- 205 of 206 searches were in English.
- 0 of the 222 cited pages were in the question's language.
Local topic (metro fare, this week's news, restaurants in Seoul, Tokyo, Madrid, Kyiv), 5 runs per question:
| Claude Code | Codex | |
|---|---|---|
| Asked in the local language: searches in that language | 82% | 50% |
| Asked in English: searches in the local language | 49% | 17% |
- Asked in English about Tokyo, Codex searched in Japanese 1 time out of 56.
- Madrid was the exception for both: even in English, most cited pages were Spanish (Claude 42 of 53, Codex 26 of 31).
- Asked in Ukrainian for Ukraine's news, all 15 links Codex cited were English-language outlets.
- All 320 answers came back in the language of the question, so you usually can't tell from the answer which language the sources were in.
Why it matters: if you publish in a language other than English, AI agents may only find you for local topics. For global topics, the English web wins.
Every query, cited URL and the language of each cited page are in the dataset (CSV/JSON, CC BY 4.0): https://tokensave.app/data/claude-web-search-by-language
來源：DEV Community · dev.to