Configure

Voice languages

Your voice agent speaks and understands 30+ languages natively — no cascading speech-to-text, translation, and text-to-speech pipeline, no extra latency. One language directive goes into the realtime model’s system prompt and the model handles the rest: transcribes in the target language, understands in the target language, responds in the target language.

The languages on offer depend on your voice model (set per organization). Gemini Live auto-detects the spoken language and switches naturally, so a chosen language is a hint rather than a hard lock; xAI Grok and OpenAI Realtime honour a locked language. The picker shows exactly what your current model supports.

Configure per widget

In Widget → Customize → AI agent, tick Enable voice chat. A Languages panel appears below the toggle with three controls, shown in the panel below. The provider line at the top names your organization’s voice model and the picker underneath offers exactly the languages that model supports. The Supported languages multi-select is where you ⌘/Ctrl-click to pick a subset (leave it empty to allow all); the counter beneath it echoes “N selected” or “All languages allowed.” The Default language dropdown — whose first row is (none — use auto-detect result) — sets the lock / fallback code, and the Auto-detect from the visitor’s first utterance checkbox at the bottom toggles the detect_language tool call.

AI agent

Languages

Enable voice chat shows the voice chip in this widget’s header

Languages

Leave empty to let the agent speak any of the 30+ languages the realtime model supports. Pick a subset to restrict, and optionally set a default for unsupported requests.

Languages available for your voice model (xAI Grok).

Supported languages

🇺🇸 English (US) (en-US) 🇪🇸 Spanish (Spain) (es-ES) 🇲🇽 Spanish (Mexico) (es-MX) 🇫🇷 French (fr-FR) 🇩🇪 German (de-DE)

⌘/Ctrl-click to toggle. 2 selected.

Default language

🇪🇸 Spanish (Spain) (es-ES) ▾

Used when the session locks to one language and when auto-detect can’t decide confidently.

Auto-detect from the visitor’s first utterance

Runs detect_language once, then locks the session to the detected code.

The Languages panel under Customize → AI agent — supported set, default, and auto-detect, offering only what your voice model handles.

Setting	What it does
Supported languages	Multi-select. Empty = every language the realtime model supports is allowed. Pick a subset to restrict (e.g. only en-US + es-ES). Non-matching utterances are politely redirected to the default language.
Default language	Dropdown. Used as the session lock when Supported languages has exactly one entry, and as the fallback when auto-detect confidence is low or when the visitor speaks something outside your supported list.
Auto-detect	Checkbox. When on, the model runs a `detect_language` tool on the first utterance, locks the session to the detected BCP-47 code, and responds in that language for the rest of the call. Off = no tool call; session runs in the default (or visitor’s picked) language from the start.

Behavior matrix

Configuration	What the visitor experiences
Supported = 1, default set	Session is always in that language. If the visitor speaks another, the agent acknowledges in the locked language and continues.
Supported = many, auto-detect on	First utterance triggers `detect_language`. Session locks to the detected code (if it’s in the supported list). Otherwise switches to the default language.
Supported = many, auto-detect off, default set	Session runs in the default language. Visitor can ask to switch mid-call (“can we do this in Spanish?”) — the model calls `detect_language` again and the session re-locks.
Supported = empty, auto-detect on	No restriction. Any language the realtime model handles is accepted; the agent follows whatever the visitor speaks.
Supported = empty, auto-detect off, no default	Falls back to English (US) as the universal default so voice never hangs on a missing language.

During the call

The widget shows a small language badge in the voice control bar (🌐 ES for a locked session, 🌐 auto while auto-detect is pending).
The session record’s detectedLanguage column is set to the BCP-47 code and languageSource is set to configured, picker, or autodetect — visible on the conversation review page.
Mid-session switches work: the visitor just asks to change language and the agent complies. The language badge updates on the next turn.

Supported languages

All BCP-47 codes our curated picker offers. The upstream realtime models (xAI Grok, OpenAI gpt-realtime, Google Gemini Live) all handle these natively.

Code	Native name	English name
`en-US`	English	English (US)
`en-GB`	English	English (UK)
`es-ES`	Español	Spanish (Spain)
`es-MX`	Español	Spanish (Mexico)
`fr-FR`	Français	French
`de-DE`	Deutsch	German
`it-IT`	Italiano	Italian
`pt-PT`	Português	Portuguese
`pt-BR`	Português	Portuguese (Brazil)
`nl-NL`	Nederlands	Dutch
`sv-SE`	Svenska	Swedish
`no-NO`	Norsk	Norwegian
`da-DK`	Dansk	Danish
`fi-FI`	Suomi	Finnish
`pl-PL`	Polski	Polish
`cs-CZ`	Čeština	Czech
`tr-TR`	Türkçe	Turkish
`ru-RU`	Русский	Russian
`uk-UA`	Українська	Ukrainian
`ar-SA`	العربية	Arabic
`he-IL`	עברית	Hebrew
`hi-IN`	हिन्दी	Hindi
`bn-IN`	বাংলা	Bengali
`ja-JP`	日本語	Japanese
`ko-KR`	한국어	Korean
`zh-CN`	中文	Chinese (Simplified)
`zh-TW`	中文	Chinese (Traditional)
`th-TH`	ไทย	Thai
`vi-VN`	Tiếng Việt	Vietnamese
`id-ID`	Indonesia	Indonesian
`ms-MY`	Melayu	Malay
`fil-PH`	Filipino	Filipino
`ro-RO`	Română	Romanian
`hu-HU`	Magyar	Hungarian
`el-GR`	Ελληνικά	Greek

Troubleshooting

Agent keeps answering in English even though I selected Spanish. Check that Supported languages actually contains es-ES (or es-MX), that the Default is set to the same code, and that the widget has been re-published since you saved. Hard-refresh the page the widget lives on to invalidate the CDN cache.
Auto-detect picks the wrong language. The detect_language tool is called on the first utterance only; a two-word greeting like “hola” may resolve to a low-confidence code. Have the visitor say a full sentence, or disable auto-detect and set a default for your primary market.
Visitor speaks an unsupported language. The agent switches to your default language and politely explains. If this happens often, add that language to Supported languages.