---
title: Create and manage Passage Retrieval (CPR) models
slug: oaie5476
canonical_url: https://docs.coveo.com/en/oaie5476/
collection: leverage-machine-learning
source_format: adoc
---
# Create and manage Passage Retrieval (CPR) models

> **Important**
>
> Passage Retrieval (CPR) is a paid product extension.
> Contact [Coveo Sales](https://www.coveo.com/en/contact) or your Account Manager to add CPR to your [organization](https://docs.coveo.com/en/185/) license.

A [Passage Retrieval (CPR)](https://docs.coveo.com/en/oaie9196/) [model](https://docs.coveo.com/en/1012/) retrieves the most relevant segments of text (passages) from your dataset to help your LLM-powered application generate an output for a specific user query.

## What does a CPR model do?
When a [CPR](https://docs.coveo.com/en/oaie9196/) [model](https://docs.coveo.com/en/1012/) builds, it creates [embeddings](https://docs.coveo.com/en/oaie5277#embeddings) for the indexed items specified in the model settings and stores the embeddings in model memory.

> **Note**
>
> The model is preconfigured to rebuild and update the embeddings weekly based on when the model is created.
> Contact your Coveo Account Manager if a different build interval is required.

> **Tip**
>
> By default, content retrieval is supported only for English content.
> However, Coveo offers beta support for content retrieval in languages other than English.
> Learn more about [multilingual content retrieval and answer generation](https://docs.coveo.com/en/p5ne0024/).

![Passage Retrieval passage embedding | Coveo](https://docs.coveo.com/en/assets/images/leverage-machine-learning/cpr-embed-passage-level.png)

A [CPR](https://docs.coveo.com/en/oaie9196/) [model](https://docs.coveo.com/en/1012/) uses a pre-trained sentence transformer language model to create the [embeddings](https://docs.coveo.com/en/ncc87383/).
The language model does this by capturing relationships between words, phrases, and sentences in the dataset.

A [CPR](https://docs.coveo.com/en/oaie9196/) [model](https://docs.coveo.com/en/1012/) creates [embeddings](https://docs.coveo.com/en/ncc87383/) only for the content in an [item](https://docs.coveo.com/en/210/)'s body, which is the content [mapped](https://docs.coveo.com/en/217/) to the `body` field in the Coveo [index](https://docs.coveo.com/en/204/).
For more information, learn [how CPR uses your content](https://docs.coveo.com/en/oaod5329#how-cpr-uses-your-content).

> **Note**
>
> The [CPR](https://docs.coveo.com/en/oaie9196/) [model](https://docs.coveo.com/en/1012/) uses only the content in an item's `body` field.
> Content in other searchable fields, such as `title`, `author`, `source`, and `date`, isn't embedded by the [model](https://docs.coveo.com/en/1012/) and therefore isn't considered during passage retrieval.
> Passages are retrieved solely based on the semantic similarity between the query and the content of an item's body.
> For example, even if a query matches terms in an item's `title` field, the [CPR](https://docs.coveo.com/en/oaie9196/) model won't retrieve passages from that item unless the body content is semantically relevant.

As shown in the following diagram, the model uses [chunks](https://docs.coveo.com/en/oaie5277#chunking) to create the [embeddings](https://docs.coveo.com/en/ncc87383/).
Instead of creating a vector for each individual word, a vector is created for a segment of text (chunk) to increase relevance.

> **Note**
>
> You can [choose the chunking strategy](https://docs.coveo.com/en/oaie5476#set-the-chunking-strategy) that the [CPR](https://docs.coveo.com/en/oaie9196/) [model](https://docs.coveo.com/en/1012/) uses to create the chunks.

![Vector space | Coveo](https://docs.coveo.com/en/assets/images/leverage-machine-learning/cpr-chunk-example.png)

As shown in the following diagram, when a user enters a [query](https://docs.coveo.com/en/231/) in a LLM-powered application, the [CPR](https://docs.coveo.com/en/oaie9196/) [model](https://docs.coveo.com/en/1012/) embeds the query in the [embedding](https://docs.coveo.com/en/ncc87383/) vector space in its memory to find the most relevant passages ([chunks](https://docs.coveo.com/en/oaie5277#chunking)).
In the context of the CPR passage retrieval flow, this is referred to as [second-stage content retrieval](https://docs.coveo.com/en/oaie5277#second-stage-content-retrieval).
Only the passages corresponding to the most relevant items identified during [first-stage content retrieval](https://docs.coveo.com/en/oaie5277#first-stage-content-retrieval) (items retrieved by the Coveo search engine) are considered.
The most relevant passages are then exposed by the Passage Retrieval API to the LLM so it can generate an answer.

![Vector space query | Coveo](https://docs.coveo.com/en/assets/images/leverage-machine-learning/grouped-cpr.png)

> **Tip**
>
> The embeddings that are created by the [CPR](https://docs.coveo.com/en/oaie9196/) [model](https://docs.coveo.com/en/1012/) aren't impacted by [Coveo Analytics events](https://docs.coveo.com/en/260/).
> However, a [CPR](https://docs.coveo.com/en/oaie9196/) [model](https://docs.coveo.com/en/1012/) leverages the most relevant items retrieved by your Coveo-powered search for a given user query.
> Therefore, by enabling an [Automatic Relevance Tuning (ART)](https://docs.coveo.com/en/1013/) [model](https://docs.coveo.com/en/1012/), which learns from [events](https://docs.coveo.com/en/260/), then the most relevant items, and by extension the generated output by your LLM, will be influenced by events.

> **Note**
>
> You can set a custom value for the maximum number of items that the CPR model considers when retrieving the most relevant segments of text (passages).
> This is an advanced [model](https://docs.coveo.com/en/1012/) query pipeline association configuration that should be used by experienced Coveo administrators only.
> For more information, see [CPR model association advanced configuration](https://docs.coveo.com/en/oaie6403#cpr-model-association-advanced-configuration).

## Prerequisites

* You have the [required privileges](#required-privileges) to create a [CPR](https://docs.coveo.com/en/oaie9196/) [model](https://docs.coveo.com/en/1012/).

* The content you want to use for the [model](https://docs.coveo.com/en/1012/) meets the [item requirements](https://docs.coveo.com/en/oaod5329#requirements) and is [optimized](https://docs.coveo.com/en/oaod5329#best-practices) for CPR.

> **Note**
>
> A [Passage Retrieval (CPR)](https://docs.coveo.com/en/oaie5277/) implementation must include both a [CPR](https://docs.coveo.com/en/oaie9196/) [model](https://docs.coveo.com/en/1012/) and a [Semantic Encoder (SE)](https://docs.coveo.com/en/nbtb0041/) [model](https://docs.coveo.com/en/1012/).
> The same SE model can be used with multiple CPR models.
> Both the CPR and SE models must be configured to use the same content.
> 
> See [CPR overview](https://docs.coveo.com/en/oaie5277#cpr-overview) for information on how CPR and SE work together in the context of a user query to retrieve passages.

> **Important**
>
> Keep the [model embedding limits](#model-embedding-limits) in mind when choosing the content for your model.

## Create a CPR model

. On the [**Models**](https://platform.cloud.coveo.com/admin/#/orgid/ai-and-ml/models/) ([platform-ca](https://platform-ca.cloud.coveo.com/admin/#/orgid/ai-and-ml/models/) | [platform-eu](https://platform-eu.cloud.coveo.com/admin/#/orgid/ai-and-ml/models/) | [platform-au](https://platform-au.cloud.coveo.com/admin/#/orgid/ai-and-ml/models/)) page of the [Coveo Administration Console](https://docs.coveo.com/en/183/), click **Add model**, and then click the **Passage Retrieval** card.

. Click **Next**.

. In the **Learn from** section, select the content that the model will use.
You can select the sources and apply additional filters using the **Standard** configuration, or use **Advanced** mode to define a custom filter expression.

> **Important**
>
> You'll lose the current mode settings when you switch between **Standard** and **Advanced** mode.

> **Note**
>
> A [Passage Retrieval (CPR)](https://docs.coveo.com/en/oaie5277/) implementation must include both a [CPR](https://docs.coveo.com/en/oaie9196/) [model](https://docs.coveo.com/en/1012/) and a [Semantic Encoder (SE)](https://docs.coveo.com/en/nbtb0041/) [model](https://docs.coveo.com/en/1012/).
> The same SE model can be used with multiple CPR models.
> Both the CPR and SE models must be configured to use the same content.
> 
> See [CPR overview](https://docs.coveo.com/en/oaie5277#cpr-overview) for information on how CPR and SE work together in the context of a user query to retrieve passages.

> **Tip**
>
> The **Data volume preview** section shows the impact of your settings on the data that's available to the model.

** In the **Standard** tab:

.. In the **Sources** dropdown menu, select the [sources](https://docs.coveo.com/en/246/) that contain the [items](https://docs.coveo.com/en/210/) from which you want the model to learn.

--
> **Note**
>
> If your Coveo organization includes [multiple indexes](https://docs.coveo.com/en/2877/), the model can learn only from sources that are linked to the default index.
--

.. (Optional) In the **Apply filters on dataset** section, you can specify a condition to segment the content on which the model should base its training:

**Example**

You want the model to base its training only on items for which the **collection** [field](https://docs.coveo.com/en/200/) have the `FAQ` value.

Therefore, you add a `collection is equal to FAQ` condition.

... Click **Add filter(s)**.

... In the **Field name** input, enter the name of the [field](https://docs.coveo.com/en/200/) that you want to use to segment the dataset.

... In the **Select an operator** dropdown menu, select the desired operator.

... In the **Value** input, enter the value of the field on which you want to segment the dataset.

... Click **Apply**.

** In the **Advanced** tab:

.. Enter a custom filter expression using [Coveo query syntax](https://docs.coveo.com/en/1552/).

.. Click **Apply**.

. Click **Next**.

. In the **Name your model** input, enter a meaningful display name for the model.

. (Optional) Use the **Project** selector to associate your model with one or more [projects](https://docs.coveo.com/en/n7ef0517/).

. Click **Start building**.

. [Associate the model with a pipeline](https://docs.coveo.com/en/oaie6403/) to use the [model](https://docs.coveo.com/en/1012/) in a search interface.

. If required, [change the chunking strategy](#set-the-chunking-strategy) that's used by the [model](https://docs.coveo.com/en/1012/).

## Set the chunking strategy

To [create the embeddings](#what-does-a-cpr-model-do), a [CPR](https://docs.coveo.com/en/oaie9196/) [model](https://docs.coveo.com/en/1012/) uses a process called chunking to break large pieces of text into smaller segments called chunks.
The method that's used to create the chunks is referred to as the chunking strategy.

The [CPR](https://docs.coveo.com/en/oaie9196/) [model](https://docs.coveo.com/en/1012/) offers two chunking strategies to choose from:

* [Structure-aware chunking](https://docs.coveo.com/en/p9ub0044#structure-aware-chunking)

* [Fixed-size chunking](https://docs.coveo.com/en/p9ub0044#fixed-size-chunking)

> **Note**
>
> [CPR](https://docs.coveo.com/en/oaie9196/) [models](https://docs.coveo.com/en/1012/) created after the release of structure-aware chunking (October 2025) use the structure-aware chunking strategy by default.
> [CPR](https://docs.coveo.com/en/oaie9196/) [models](https://docs.coveo.com/en/1012/) created before October 2025 use the fixed-size chunking strategy by default.
> 
> To view a [CPR](https://docs.coveo.com/en/oaie9196/) [model](https://docs.coveo.com/en/1012/)'s active chunking strategy, on the [**Models**](https://platform.cloud.coveo.com/admin/#/orgid/ai-and-ml/models/) ([platform-ca](https://platform-ca.cloud.coveo.com/admin/#/orgid/ai-and-ml/models/) | [platform-eu](https://platform-eu.cloud.coveo.com/admin/#/orgid/ai-and-ml/models/) | [platform-au](https://platform-au.cloud.coveo.com/admin/#/orgid/ai-and-ml/models/)) page, click the [CPR](https://docs.coveo.com/en/oaie9196/) [model](https://docs.coveo.com/en/1012/), and then click **View JSON** in the Action bar.
> The chunking strategy appears in the `strategy` parameter of the `chunkerConfig` object under `extraConfig`.

> **Important**
>
> Structure-aware chunking is specifically optimized for large language [models](https://docs.coveo.com/en/1012/) (LLMs) and [RAG](https://docs.coveo.com/en/p8ie0159/) systems, and is the recommended chunking strategy.
> You should use structure-aware chunking unless you have a [specific use case that requires](https://docs.coveo.com/en/p9ub0044#choosing-a-chunking-strategy) the use of fixed-size chunking.

> **Note**
>
> You can configure each CPR model to use a different chunking strategy depending on your specific needs.

To set the model chunking strategy

> **Important**
>
> Modifying the chunking strategy initiates an automatic [model](https://docs.coveo.com/en/1012/) [rebuild](https://docs.coveo.com/en/2712/).

> **Note**
>
> Review the [main considerations](https://docs.coveo.com/en/p9ub0044#choosing-a-chunking-strategy) when choosing between chunking strategies.

. Access the **Machine Learning** section of the Swagger UI that's associated with your Coveo organization region ([US](https://platform.cloud.coveo.com/docs?urls.primaryName=Machine+Learning) | [CA](https://platform-ca.cloud.coveo.com/docs?urls.primaryName=Machine+Learning) | [EU](https://platform-eu.cloud.coveo.com/docs?urls.primaryName=Machine+Learning) | [AU](https://platform-au.cloud.coveo.com/docs?urls.primaryName=Machine+Learning)).

. Click **Authorize** and authenticate using your Coveo organization account credentials.

. In the Swagger UI, expand the **Machine Learning Models** section.

. Use the **List all models** GET request to access your model's JSON code:

![Use Swagger UI to get a list of CPR models | Coveo](https://docs.coveo.com/en/assets/images/leverage-machine-learning/cpr-model-swagger-list-request.png)

.. Enter your Coveo [**organization ID**](https://docs.coveo.com/en/n1ce5273/).

.. Enter the `chunksretrieval` **engine ID** to filter the list to show only [CPR](https://docs.coveo.com/en/oaie9196/) [models](https://docs.coveo.com/en/1012/).

.. Click **Execute**.
The JSON code for all [CPR](https://docs.coveo.com/en/oaie9196/) [models](https://docs.coveo.com/en/1012/) in your organization appears in the **Response body**.

.. In the **Response body**, copy the JSON code of the [model](https://docs.coveo.com/en/1012/) that you want to configure.
You'll need it in the next step.

. Use the **Update the configuration of a model** PUT request to modify the [model](https://docs.coveo.com/en/1012/)'s JSON code:

![Use Swagger UI to edit a CPR machine learning model | Coveo](https://docs.coveo.com/en/assets/images/leverage-machine-learning/cpr-model-swagger-put-request.png)

.. Paste the copied JSON code in the **Request body**.

.. Enter your Coveo **organization ID**.

.. Enter the ID of the [model](https://docs.coveo.com/en/1012/) you want to modify.

> **Tip**
>
> If you don't know the model ID, it appears in the [model](https://docs.coveo.com/en/1012/)'s JSON code in the `id` field.

.. In the `extraConfig` element, add the `chunkerConfig` object, and then add the `strategy` parameter, and set it to either `FIXED_SIZE` or `STRUCTURE_AWARE`.

**Example**

To set the structure-aware chunking strategy, the JSON is as follows:

```json
{
...
"extraConfig": {
    "chunkerConfig": {
        "strategy": "STRUCTURE_AWARE"
    }
    }
...
}
```

. In the Swagger UI, click **Execute** to apply the changes to the [model](https://docs.coveo.com/en/1012/).

## Set the maximum chunks per item

By default, a [CPR](https://docs.coveo.com/en/oaie9196/) [model](https://docs.coveo.com/en/1012/) is configured to create a maximum of 1000 chunks per item during the [embedding process](#what-does-a-cpr-model-do).
The default setting is suitable for the majority of use cases.
However, if you have a large dataset, you can lower the maximum number of chunks per item to avoid the [model](https://docs.coveo.com/en/1012/) exceeding the overall [model embedding limit](#model-embedding-limits) for chunks.

> **Important**
>
> The [model](https://docs.coveo.com/en/1012/) will embed the item's text until the maximum chunks per item limit is reached.
> The remaining text in the item won't be embedded and therefore won't be used by the [model](https://docs.coveo.com/en/1012/).
> 
> To make sure that each item's text is fully embedded, follow [best practices](https://docs.coveo.com/en/oaod5329#best-practices) by keeping items concise and focused.

To set the maximum number of chunks per item

. Access the **Machine Learning** section of the Swagger UI that's associated with your Coveo organization region ([US](https://platform.cloud.coveo.com/docs?urls.primaryName=Machine+Learning) | [CA](https://platform-ca.cloud.coveo.com/docs?urls.primaryName=Machine+Learning) | [EU](https://platform-eu.cloud.coveo.com/docs?urls.primaryName=Machine+Learning) | [AU](https://platform-au.cloud.coveo.com/docs?urls.primaryName=Machine+Learning)).

. Click **Authorize** and authenticate using your Coveo organization account credentials.

. In the Swagger UI, expand the **Machine Learning Models** section.

. Use the **List all models** GET request to access your model's JSON code:

![Use Swagger UI to get a list of CPR models | Coveo](https://docs.coveo.com/en/assets/images/leverage-machine-learning/cpr-model-swagger-list-request.png)

.. Enter your Coveo [**organization ID**](https://docs.coveo.com/en/n1ce5273/).

.. Enter the `chunksretrieval` **engine ID** to filter the list to show only [CPR](https://docs.coveo.com/en/oaie9196/) [models](https://docs.coveo.com/en/1012/).

.. Click **Execute**.
The JSON code for all [CPR](https://docs.coveo.com/en/oaie9196/) [models](https://docs.coveo.com/en/1012/) in your organization appears in the **Response body**.

.. In the **Response body**, copy the JSON code of the [model](https://docs.coveo.com/en/1012/) that you want to configure.
You'll need it in the next step.

. Use the **Update the configuration of a model** PUT request to modify the [model](https://docs.coveo.com/en/1012/)'s JSON code:

![Use Swagger UI to edit a CPR machine learning model | Coveo](https://docs.coveo.com/en/assets/images/leverage-machine-learning/cpr-model-swagger-put-request.png)

.. Paste the copied JSON code in the **Request body**.

.. Enter your Coveo **organization ID**.

.. Enter the ID of the [model](https://docs.coveo.com/en/1012/) you want to modify.

> **Tip**
>
> If you don't know the [model](https://docs.coveo.com/en/1012/) ID, it appears in the [model](https://docs.coveo.com/en/1012/)'s JSON code in the `id` field.

.. In the `extraConfig` element, under the `chunkerConfig` object, add the `maxPassagesPerDocument` parameter, and set it to a value between `1` and `1000` (default).

**Example**

To set the maximum number of chunks per item to 500, the JSON is as follows:

```json
{
...
"extraConfig": {
    "chunkerConfig": {
        "strategy": "STRUCTURE_AWARE",
        "maxPassagesPerDocument": 500
    }
    }
...
}
```

> **Note**
>
> Once you modify the [model](https://docs.coveo.com/en/1012/)'s default value, you can view the set value by going to the [**Models**](https://platform.cloud.coveo.com/admin/#/orgid/ai-and-ml/models/) ([platform-ca](https://platform-ca.cloud.coveo.com/admin/#/orgid/ai-and-ml/models/) | [platform-eu](https://platform-eu.cloud.coveo.com/admin/#/orgid/ai-and-ml/models/) | [platform-au](https://platform-au.cloud.coveo.com/admin/#/orgid/ai-and-ml/models/)) page, clicking the [CPR](https://docs.coveo.com/en/oaie9196/) [model](https://docs.coveo.com/en/1012/), and then clicking **View JSON** in the Action bar.
> The value appears in the `maxPassagesPerDocument` parameter of the `chunkerConfig` object under `extraConfig`.

. In the Swagger UI, click **Execute** to apply the changes to the [model](https://docs.coveo.com/en/1012/).

## Manage a CPR model

You can [edit](#edit-a-cpr-model), [delete](#delete-a-cpr-model), or [review information](#review-model-information) for your [model](https://docs.coveo.com/en/1012/).

### Edit a CPR model

. On the [**Models**](https://platform.cloud.coveo.com/admin/#/orgid/ai-and-ml/models/) ([platform-ca](https://platform-ca.cloud.coveo.com/admin/#/orgid/ai-and-ml/models/) | [platform-eu](https://platform-eu.cloud.coveo.com/admin/#/orgid/ai-and-ml/models/) | [platform-au](https://platform-au.cloud.coveo.com/admin/#/orgid/ai-and-ml/models/)) page, click the model you want to edit, and then click **Edit** in the Action bar.

. On the subpage that opens, select the **Configuration** tab.

. Under **Name**, edit the model's display name.

. (Optional) Use the **Project** selector to associate your model with one or more [projects](https://docs.coveo.com/en/n7ef0517/).

. In the **Learn from** section, select the content that the model will use.
You can select the sources and apply additional filters using the **Standard** configuration or use **Advanced** mode to define a custom filter expression.

> **Important**
>
> You'll lose the current mode settings when you switch between **Standard** and **Advanced** mode.

> **Note**
>
> A [Passage Retrieval (CPR)](https://docs.coveo.com/en/oaie5277/) implementation must include both a [CPR](https://docs.coveo.com/en/oaie9196/) [model](https://docs.coveo.com/en/1012/) and a [Semantic Encoder (SE)](https://docs.coveo.com/en/nbtb0041/) [model](https://docs.coveo.com/en/1012/).
> The same SE model can be used with multiple CPR models.
> Both the CPR and SE models must be configured to use the same content.
> 
> See [CPR overview](https://docs.coveo.com/en/oaie5277#cpr-overview) for information on how CPR and SE work together in the context of a user query to retrieve passages.

> **Tip**
>
> The **Data volume preview** section shows the impact of your settings on the data that's available to the model.

** In the **Standard** tab:

.. In the **Sources** dropdown menu, select the [sources](https://docs.coveo.com/en/246/) that contain the [items](https://docs.coveo.com/en/210/) from which you want the model to learn.

--
> **Note**
>
> If your Coveo organization includes [multiple indexes](https://docs.coveo.com/en/2877/), the model can learn only from sources that are linked to the default index.
--

.. (Optional) In the **Apply filters on dataset** section, you can specify a condition to segment the content on which the model should base its training:

**Example**

You want the model to base its training only on items for which the **collection** [field](https://docs.coveo.com/en/200/) have the `FAQ` value.

Therefore, you add a `collection is equal to FAQ` condition.

... Click **Add filter(s)**.

... In the **Field name** input, enter the name of the [field](https://docs.coveo.com/en/200/) that you want to use to segment the dataset.

... In the **Select an operator** dropdown menu, select the desired operator.

... In the **Value** input, enter the value of the field on which you want to segment the dataset.

... Click **Apply**.

** In the **Advanced** tab:

.. Enter a custom filter expression using [Coveo query syntax](https://docs.coveo.com/en/1552/).

.. Click **Apply**.

. Click **Save**.

> **Note**
>
> Some configuration changes initiate an automatic model rebuild when you save the model.
> The [**Models**](https://platform.cloud.coveo.com/admin/#/orgid/ai-and-ml/models/) ([platform-ca](https://platform-ca.cloud.coveo.com/admin/#/orgid/ai-and-ml/models/) | [platform-eu](https://platform-eu.cloud.coveo.com/admin/#/orgid/ai-and-ml/models/) | [platform-au](https://platform-au.cloud.coveo.com/admin/#/orgid/ai-and-ml/models/)) page shows your model's current **Status**.
> Model settings take effect only when its status is **Active**.
> 
> For more information on Coveo ML model statuses, see the [**Status** column reference](#status-column).

### Delete a CPR model

> **Note**
>
> If the model is associated with a query pipeline, make sure to dissociate the model from the query pipeline after deleting it.

. On the [**Models**](https://platform.cloud.coveo.com/admin/#/orgid/ai-and-ml/models/) ([platform-ca](https://platform-ca.cloud.coveo.com/admin/#/orgid/ai-and-ml/models/) | [platform-eu](https://platform-eu.cloud.coveo.com/admin/#/orgid/ai-and-ml/models/) | [platform-au](https://platform-au.cloud.coveo.com/admin/#/orgid/ai-and-ml/models/)) page, click the ML model that you want to delete, and then click **More** > **Delete** in the Action bar.

. In the panel that appears, click **Delete**.

### Review model information

On the [**Models**](https://platform.cloud.coveo.com/admin/#/orgid/ai-and-ml/models/) ([platform-ca](https://platform-ca.cloud.coveo.com/admin/#/orgid/ai-and-ml/models/) | [platform-eu](https://platform-eu.cloud.coveo.com/admin/#/orgid/ai-and-ml/models/) | [platform-au](https://platform-au.cloud.coveo.com/admin/#/orgid/ai-and-ml/models/)) page, click the desired model, and then click **View** in the Action bar.
For more information, see [Reviewing model information](https://docs.coveo.com/en/1894/).

## Model embedding limits

The [CPR](https://docs.coveo.com/en/oaie9196/) [model](https://docs.coveo.com/en/1012/) converts your content's body text into numerical representations ([vectors](https://docs.coveo.com/en/nccf9008/)) in a process called [embedding](https://docs.coveo.com/en/ncc87383/).
It does this by breaking the text up into smaller segments called chunks, and each chunk is mapped as a distinct vector.
For more information, see [Embeddings](https://docs.coveo.com/en/oaie5277#embeddings).

Due to the amount of processing required for embeddings, the model is subject to the following embedding limits,depending on the [chunking strategy](https://docs.coveo.com/en/p9ub0044/).

> **Note**
>
> For a given [model](https://docs.coveo.com/en/1012/), the same chunking strategy is used for all sources and item types.

[cols="1,1,1",options="header"]
|===
| Limit
| Structure-aware chunking
| Fixed-size chunking

| Chunk size
| Average of 300 tokens per chunk  
(minimum: 200 tokens; maximum: 400 tokens)
| 250 whitespace-delimited words per chunk

| Maximum number of items or chunks
2+a| Up to 15 million items or 50 million chunks  
> **Notes**
>
> * The maximum number of items depends on the [item allocation of your product plan](https://docs.coveo.com/en/l2590456#generative-ai-solutions).
> 
> * Your CPR implementation must include a [Semantic Encoder (SE) model](https://docs.coveo.com/en/nb6a0483/).
> If you have more than one CPR model in your Coveo organization, each CPR model must use only the items that are used by the SE model.

| Maximum number of chunks per item
2+a| 1000 (default)  
> **Note**
>
> The default setting of 1000 is suitable for the majority of use cases.
> If required, you can [set a custom value between `1` and `1000`](https://docs.coveo.com/en/oaie5476#set-the-maximum-chunks-per-item).

> **Important**
>
> The [model](https://docs.coveo.com/en/1012/) will embed the item's text until the maximum chunks per item limit is reached.
> The remaining text in the item won't be embedded and therefore won't be used by the [model](https://docs.coveo.com/en/1012/).
> 
> To make sure that each item's text is fully embedded, follow [best practices](https://docs.coveo.com/en/oaod5329#best-practices) by keeping items concise and focused.
|===

## "Status" column

On the [**Models**](https://platform.cloud.coveo.com/admin/#/orgid/ai-and-ml/models/) ([platform-ca](https://platform-ca.cloud.coveo.com/admin/#/orgid/ai-and-ml/models/) | [platform-eu](https://platform-eu.cloud.coveo.com/admin/#/orgid/ai-and-ml/models/) | [platform-au](https://platform-au.cloud.coveo.com/admin/#/orgid/ai-and-ml/models/)) page of the [Administration Console](https://docs.coveo.com/en/183/), the **Status** column indicates the current state of your Coveo ML models.

The following table lists the possible model statuses and their definitions:

[%header,cols="1,6,^.^1"]
|===
.^|Status
.^|Definition
|Status icon

|Active
|The model is active and available.
a|![Active](leverage-machine-learning/model-active.png)

|Build in progress
|The model is currently building.
a|![Building](leverage-machine-learning/model-build.png)

|Inactive
|The model isn't ready to be queried, such as when a model was recently created or the organization is offline.  
Click **See more details** for additional information (see [Review model information](https://docs.coveo.com/en/1894/)).
a|![Inactive](leverage-machine-learning/model-limited.png)

|Limited
|Build issues exist that may affect model performance.  
Click **See more details** for additional information (see [Review model information](https://docs.coveo.com/en/1894/)).
a|![Limited](leverage-machine-learning/model-limited.png)

|Soon to be archived
|The model will soon be archived because it hasn't been queried for an extended period of time.  
Click **Delete** to remove the model.  
[Learn more about archived models](https://docs.coveo.com/en/mb3e0324/).
a|![Archive pending](leverage-machine-learning/model-limited.png)

|Error
|An error prevented the model from being built successfully.  
If it's a temporary system error, check back soon.
Otherwise, click **See more details** for additional information (see [Review model information](https://docs.coveo.com/en/1894/)).
a|![Error](leverage-machine-learning/model-error.png)

|Archived
|The model was archived because it hasn't been queried for an extended period of time.  
Click **Delete** to remove the model.  
[Learn more about archived models](https://docs.coveo.com/en/mb3e0324/).
a|![Archived](leverage-machine-learning/model-archived.png)
|===

## Required privileges

By default, members with the [required privileges](https://docs.coveo.com/en/1832#required-privileges) can view and edit elements of the [**Models**](https://platform.cloud.coveo.com/admin/#/orgid/ai-and-ml/models/) ([platform-ca](https://platform-ca.cloud.coveo.com/admin/#/orgid/ai-and-ml/models/) | [platform-eu](https://platform-eu.cloud.coveo.com/admin/#/orgid/ai-and-ml/models/) | [platform-au](https://platform-au.cloud.coveo.com/admin/#/orgid/ai-and-ml/models/)) page.

The following table indicates the privileges required for members to manage Coveo Generic models (see [Manage privileges](https://docs.coveo.com/en/3151/) and [Privilege reference](https://docs.coveo.com/en/1707/)).

[cols="3",options="header"]
|===
|Action
|Service - Domain
|Required access level

|View models
|Machine Learning - Models  
Organization - Organization  
Search - Query pipelines
|View

.5+|Manage models
|Organization - Organization  
Search - Query pipelines
|View

|Machine Learning - Models
|Edit

|Machine Learning - Allow content preview
|Enable

|Content - Sources
|View All

|Content - Fields
|View
|===

## What's next?

[Associate the CPR model with a query pipeline](https://docs.coveo.com/en/oaie6403/).