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

# genai_concat_contents

> This page explains how to use the genai_concat_contents function in APL.

The `genai_concat_contents` function concatenates all message contents from a GenAI conversation array into a single string. This is useful when you need to combine multiple conversation messages into a single text field for analysis, full-text search, or creating a complete conversation transcript.

You can use this function to create searchable conversation transcripts, prepare data for analysis, or consolidate conversation history for reporting.

## For users of other query languages

If you come from other query languages, this section explains how to adjust your existing queries to achieve the same results in APL.

<AccordionGroup>
  <Accordion title="Splunk SPL users">
    In Splunk SPL, you would typically use multiple `eval` commands with `mvjoin` to concatenate array values, but there’s no direct equivalent for extracting and joining message contents from nested structures.

    <CodeGroup>
      ```sql Splunk example theme={null}
      | eval all_content=mvjoin(messages, " ")
      ```

      ```kusto APL equivalent theme={null}
      ['ai-logs']
      | extend all_content = genai_concat_contents(messages, ' ')
      ```
    </CodeGroup>
  </Accordion>

  <Accordion title="ANSI SQL users">
    In ANSI SQL, you would need to unnest the array and use `STRING_AGG` or similar functions to concatenate values, which is more verbose.

    <CodeGroup>
      ```sql SQL example theme={null}
      SELECT 
        conversation_id,
        STRING_AGG(content, ' ') as all_content
      FROM conversations
      CROSS JOIN UNNEST(messages) as msg
      GROUP BY conversation_id
      ```

      ```kusto APL equivalent theme={null}
      ['ai-logs']
      | extend all_content = genai_concat_contents(messages, ' ')
      ```
    </CodeGroup>
  </Accordion>
</AccordionGroup>

## Usage

### Syntax

```kusto theme={null}
genai_concat_contents(messages, separator)
```

### Parameters

| Name      | Type    | Required | Description                                                                                                          |
| --------- | ------- | -------- | -------------------------------------------------------------------------------------------------------------------- |
| messages  | dynamic | Yes      | An array of message objects from a GenAI conversation. Each message typically contains a `role` and `content` field. |
| separator | string  | No       | The string used to separate message contents. Default is a space character (`' '`).                                  |

### Returns

Returns a string containing all message contents concatenated together with the specified separator.

## Example

Create a searchable conversation transcript from a GenAI conversation array.

**Query**

```kusto theme={null}
['otel-demo-genai']
| extend conversation_text = genai_concat_contents(['attributes.gen_ai.input.messages'], ' / ')
```

[Run in Playground](https://play.axiom.co/axiom-play-qf1k/query?initForm=%7B%22apl%22%3A%22%5B%27otel-demo-genai%27%5D%20%7C%20extend%20conversation_text%20%3D%20genai_concat_contents\(%5B%27attributes.gen_ai.input.messages%27%5D%2C%20%27%20%2F%20%27\)%22%7D)

**Output**

| conversation\_text                                                                                                                               |
| ------------------------------------------------------------------------------------------------------------------------------------------------ |
| "Hello, how are you? / I'm good, thank you! / What's your name? / My name is John. / What's your favorite color? / My favorite color is blue. /" |

This query concatenates the message contents of a GenAI conversation array with a separator of `/`.

## List of related functions

* [genai\_extract\_user\_prompt](/apl/scalar-functions/genai-functions/genai-extract-user-prompt): Extracts only the user's prompt instead of all messages. Use this when you need just the user's input.
* [genai\_extract\_assistant\_response](/apl/scalar-functions/genai-functions/genai-extract-assistant-response): Extracts only the assistant's response. Use this when you need just the AI's output.
* [genai\_get\_content\_by\_role](/apl/scalar-functions/genai-functions/genai-get-content-by-role): Gets content filtered by a specific role. Use this when you need messages from a particular role like 'system' or 'tool'.
* [genai\_message\_roles](/apl/scalar-functions/genai-functions/genai-message-roles): Extracts all message roles from a conversation. Use this to understand the conversation structure.
* [strcat\_array](/apl/scalar-functions/array-functions/strcat-array): Concatenates a simple string array. Use this for non-GenAI arrays that don't have the message structure.