> ## Documentation Index > Fetch the complete documentation index at: https://docs-classic.cognigy.com/llms.txt > Use this file to discover all available pages before exploring further. # OpenAI [Updated in 2026.22](https://docs-classic.cognigy.com/release-notes/2026.22.md) > [!WARNING] > > As of Cognigy 2026.6.0, the support for the Completions API for custom LLMs is deprecated. The full removal is planned for Cognigy 2026.24.0. Switch to the \`[https://api.openai.com/v1/chat/completions\`](https://api.openai.com/v1/chat/completions`) API instead before the removal date. > [!NOTE] > > The `gpt-5-1`, `gpt-5-2`, `gpt-5-4`, `gpt-5-4-mini`, `gpt-5-4-nano`, `gpt-5-5`, `gpt-5-6-sol`, `gpt-5-6-terra`, `gpt-5-6-luna`, `gpt-6-sol`, `gpt-6-luna`, and `gpt-6-1-sol` models default to `reasoning.effort: "low"` on the Responses API. The `reasoning.effort` parameter controls how much effort the model uses to think through a request. Higher effort can help the model handle more complex requests, while lower effort can yield faster responses. Supported values, such as `"none"`, `"low"`, `"medium"`, and `"high"`, and their behavior can vary by model and API. Check your LLM provider's documentation for supported values and behavior. > > To override this default value, set `reasoning.effort` in **Custom Model Options**. > > The default `temperature` is `1.0`. To override this value, you must set `reasoning.effort: "none"` and adjust the **Temperature** parameter or set `temperature` in **Custom Model Options**. To start using an OpenAI model with Cognigy features, follow these steps: 1. [Add Models](#add-models) 2. [Apply the Model](#apply-the-model) ## Restrictions * The `gpt-5-5`, `gpt-5-6-sol`, `gpt-5-6-terra`, `gpt-5-6-luna`, `gpt-6-sol`, `gpt-6-luna`, and `gpt-6-1-sol` models support only the Responses API. * The `gpt-6-1-sol` model doesn't support the `"none"` and `"minimal"` values for `reasoning.effort`. As a result, you can't override its default `temperature`. ## Add Models You can add a model using one of the following interfaces: * [GUI](#add-models-via-gui) * [API](#add-models-via-the-api) ### Add Models via GUI You can add a model provided by OpenAI to Cognigy in **Build > LLM**. To add the model, you will need the following parameters: > [tab] Standard Model > > | Parameter | Description | > | - | - | > | apiKey | Add an API Key from your OpenAI account. You can find this key in the [User settings](https://help.openai.com/en/articles/4936850-where-do-i-find-my-secret-api-key) of your OpenAI account. | > | API Type | Select the API format for chat models. **Chat Completion** uses the [Chat Completions API](https://platform.openai.com/docs/api-reference/chat). **Responses** uses the [Responses API](https://platform.openai.com/docs/api-reference/responses). The default is **Chat Completion**. This option is only available for chat models that support both API types. | > [tab] Custom Model > > | Parameter | Description | > | - | - | > | Model Type | Select one of the following options: For more information, refer to the [OpenAI Text Generation Models](https://platform.openai.com/docs/guides/text-generation) documentation. | > | Model Name | Enter the name of the model that you want to use as a custom model. To find model names, refer to the [OpenAI models](https://developers.openai.com/api/docs/models) documentation. | > | apiKey | Add an API Key from your OpenAI account. You can find this key in the [User settings](https://help.openai.com/en/articles/4936850-where-do-i-find-my-secret-api-key) of your OpenAI account. | > | API Type | Appears only when **Chat** is selected as the model type. Select one of the following API options for chat models: Make sure the model supports the selected API type. | 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](https://docs-classic.cognigy.com/ai/agents/develop/knowledge-ai/overview#embedding-model). To switch an embedding, delete the connection and create a new one. ### Add Models via the API You can add either a standard or custom model using the [Cognigy API POST /v2.0/largelanguagemodels](https://api-trial.cognigy.ai/openapi#post-/v2.0/largelanguagemodels) request. Then, test your connection for the created model via the [Cognigy API POST /v2.0/largelanguagemodels//test](https://api-trial.cognigy.ai/openapi#post-/v2.0/largelanguagemodels/-largeLanguageModelId-/test). ## 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](https://docs-classic.cognigy.com/ai/agents/develop/gen-ai-and-llms/model-support-by-feature.md) 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. ## More Information * [Other LLM Operations](https://docs-classic.cognigy.com/ai/agents/develop/gen-ai-and-llms/other-operations.md) * [Overview](https://docs-classic.cognigy.com/ai/agents/develop/gen-ai-and-llms/llms.md) * [All LLM Providers](https://docs-classic.cognigy.com/ai/agents/develop/gen-ai-and-llms/providers/all-providers.md) * [Model support by feature](https://docs-classic.cognigy.com/ai/agents/develop/gen-ai-and-llms/model-support-by-feature.md) * [Azure OpenAI](https://docs-classic.cognigy.com/ai/agents/develop/gen-ai-and-llms/providers/microsoft-azure-openai.md) This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.