Vertex AI Search and Conversation has been renamed to Vertex AI Agent Builder. We are in the process of updating content to reflect the new branding.

Answer generation model versions and lifecycle

Vertex AI Search offers multiple model versions for you to choose when generating answers. You can choose the model versions when using search summaries and search with follow-ups.

Generally available (GA) models

Vertex AI Search uses two types of GA models for question and answering use cases:

Vertex AI LLM models that have been tested on question and answering tasks
Vertex AI Search models that are based on Vertex AI LLM models and further trained to address question and answering tasks

Vertex AI Search models share the same discontinuation date as their base Vertex AI LLM models. The base LLM model is available for six months after the release date of the next version of the model, per the Vertex AI model lifecycle policy. Leave enough time to migrate to new models before the discontinuation dates.

The following table lists model version specifications. When you set a model specification, the API uses the specified model to generate answers.

Model version specification	Description	Context window	Discontinuation date
`stable`	The default model choice if the model version is not set. The `stable` model specification points to `text-bison@001/answer_gen/v1`, is based on the `text-bison@001` model with additional training to address question and answering tasks. The model is updated periodically with incremental improvements.	8K	The `text-bison@001` model will be deprecated on July 6, 2024. The `stable` model specification will point to a new model.
`gemini-1.0-pro-001/answer_gen/v1`	Point to the `gemini-1.0-pro-001` model The model is frozen after release.	32K	February 15, 2025
`gemini-1.0-pro-002/answer_gen/v1`	A Vertex AI Search model based on the `gemini-1.0-pro-002` model with additional training to address question and answering tasks. The model is frozen after release.	32K	Not set
`text-bison@001/answer_gen/v1`	A Vertex AI Search model based on the `text-bison@001` model with additional training to address question and answering tasks. The model is frozen after release.	8K	July 6, 2024
`text-bison@002/answer_gen/v1`	A Vertex AI Search model based on the `text-bison@002` model with additional training to address question and answering tasks. The model is frozen after release.	8K	Not set

Preview models

Preview models are new models provided by Vertex AI that you can use for question and answering tasks.

Model version specification	Description	Context window	Discontinuation date
`preview`	The `preview` model specification points to the latest `gemini-1.5-pro-preview-0409` model.	1M	Not set

Healthcare data model

When you're querying healthcare data with generative AI answers, the preview model version points to the preview model that's based on the MedLM model. For more information, see MedLM model.

What's next

Get search summaries