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Updated in 2026.11
As of Cognigy.AI 2026.6.0, the support for the Completions API for custom LLMs is deprecated. The full removal is planned for Cognigy.AI 2026.24.0.
Anthropic’s claude-sonnet-4-6 model doesn’t support assistant message prefilling. If your AI Agent uses this model and a conversation ends with an assistant message, for example, after a Say Node, requests can fail with the error The conversation must end with a user message.To keep your Flows compatible, ensure that the last transcript step before the LLM call is a user message. For example, add an Add Transcript Step Node before the LLM call and set the role to user.
To start using an Anthropic model with Cognigy.AI features, follow these steps:
  1. Add a Model
  2. Apply the Model

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Add Models

You can add a model using one of the following interfaces:

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Add Models via GUI

You can add a model provided by Anthropic to Cognigy.AI in Build > LLM. To add the model, you will need the following parameters:
The *-latest suffix indicates that the model you select points to the latest version of the model. For more information, read the Anthropic’s models documentation.
ParameterDescription
apiKeyAdd an API Key that you generated via Account Settings in Anthropic.
Apply changes. Check if the connection was set up by clicking Test. You can switch generative models at any time using the Model list without setting up a new connection. For embedding models, the selection is locked because different embedding models can generate incompatible embeddings for Knowledge AI. To switch an embedding, delete the connection and create a new one.

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Add Models via the API

You can add either a standard or custom model using the Cognigy.AI API POST /v2.0/largelanguagemodels request. Then, test your connection for the created model via the Cognigy.AI API POST /v2.0/largelanguagemodels//test.

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Apply the Model

To apply a model, follow these steps:
  1. In the left-side menu of the Project, go to Manage > Settings.
  2. Go to the section based on your use case for using a model:
    • Generative AI Settings. In the Generative AI Settings section, activate Enable Generative AI Features. This setting is toggled on by default if you have previously set up the Generative AI credentials.
    • Knowledge AI Settings. Use this section if you need to add a model for Knowledge AI. Select a model for the Knowledge Search and Answer Extraction features. Refer to the list of standard models and find the models that support these features.
  3. Navigate to the desired feature and select a model from the list. If there are no models available for the selected feature, the system will automatically select None. Save changes.

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More Information

Last modified on June 2, 2026