---
title: Language Mismatch
description: Learn about Datadog's Language Mismatch evaluation.
breadcrumbs: >-
  Docs > Agent Observability > Evaluations > Managed Evaluations > Language
  Mismatch
---

# Language Mismatch

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# Important note for users on the following Datadog sites: app.ddog-gov.com, us2.ddog-gov.com

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This product is not supported for your selected [Datadog site](https://docs.datadoghq.com/getting_started/site.md). ({% placeholder "user-datadog-site-name" /%}).
{% /alert %}

{% /callout %}

This check identifies instances where the LLM generates responses in a different language or dialect than the one used by the user, which can lead to confusion or miscommunication. This check ensures that the LLM's responses are clear, relevant, and appropriate for the user's linguistic preferences and needs.

Language mismatch is only supported for natural language prompts. Input and output pairs that mainly consist of structured data such as JSON, code snippets, or special characters are not flagged as a language mismatch.

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##### Supported languages

Afrikaans, Albanian, Arabic, Armenian, Azerbaijani, Belarusian, Bengali, Norwegian Bokmal, Bosnian, Bulgarian, Chinese, Croatian, Czech, Danish, Dutch, English, Estonian, Finnish, French, Georgian, German, Greek, Gujarati, Hebrew, Hindi, Hungarian, Icelandic, Indonesian, Irish, Italian, Japanese, Kazakh, Korean, Latvian, Lithuanian, Macedonian, Malay, Marathi, Mongolian, Norwegian Nynorsk, Persian, Polish, Portuguese, Punjabi, Romanian, Russian, Serbian, Slovak, Slovene, Spanish, Swahili, Swedish, Tamil, Telugu, Thai, Turkish, Ukrainian, Urdu, Vietnamese, Yoruba, Zulu
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{% image
   source="https://docs.dd-static.net/images/llm_observability/evaluations/language_mismatch_4.9d01ca57fa8483119413e4a000bbe77b.png?auto=format&fit=max&w=850 1x, https://docs.dd-static.net/images/llm_observability/evaluations/language_mismatch_4.9d01ca57fa8483119413e4a000bbe77b.png?auto=format&fit=max&w=850&dpr=2 2x"
   alt="A Language Mismatch evaluation detected by an open source model in Agent Observability" /%}

| Evaluation Stage              | Evaluation Method                 | Evaluation Definition                                                                                                                                                 |
| ----------------------------- | --------------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| Evaluated on Input and Output | Evaluated using Open Source Model | Language Mismatch flags whether each prompt-response pair demonstrates that the LLM application answered the user's question in the same language that the user used. |