> ## Documentation Index
> Fetch the complete documentation index at: https://docs.langchain.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Example data format

<Check>
  Before diving into this content, it might be helpful to read the following:

  * [Conceptual guide on evaluation](/langsmith/evaluation-concepts)
</Check>

LangSmith stores examples in datasets as follows:

| Field Name          | Type     | Description                                                                                          |
| ------------------- | -------- | ---------------------------------------------------------------------------------------------------- |
| **id**              | UUID     | Unique identifier for the example.                                                                   |
| **name**            | string   | The name of the example.                                                                             |
| **created\_at**     | datetime | The time this example was created                                                                    |
| **modified\_at**    | datetime | The last time this example was modified                                                              |
| **inputs**          | object   | A map of inputs for the example.                                                                     |
| **outputs**         | object   | A map or set of outputs generated by the run.                                                        |
| **dataset\_id**     | UUID     | The dataset the example belongs to                                                                   |
| **source\_run\_id** | UUID     | If this example was created from a LangSmith [`Run`](/langsmith/run-data-format), the ID of said run |
| **metadata**        | object   | A map of additional, user or SDK defined information that can be stored on an example.               |

To learn more about how examples are used in evaluation, read our how-to guide on [evaluating LLM applications](/langsmith/evaluate-llm-application).

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