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 answers and follow-ups.
Available models
Vertex AI Search uses two types of 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 | Generic | Healthcare | ||||
---|---|---|---|---|---|---|
Description | Context window | Discontinuation date | Description | Context window | Discontinuation date | |
stable |
The default model choice if the model version is not set.
The
The model designated as |
128K | N/A |
The default model choice if the model version is not set.
The
The model designated as |
128K | N/A |
gemini-1.0-pro-001/answer_gen/v1 |
Points to the The model is frozen after release. |
32K | February 15, 2025 | Not Available | ||
gemini-1.0-pro-002/answer_gen/v1 |
A Vertex AI Search based on the The model is frozen after release. |
32K | April 9, 2025 |
A Vertex AI Search model based on the The model is frozen after release. |
32K | April 9, 2025 |
gemini-1.5-flash-001/answer_gen/v1 |
A Vertex AI Search model based on the The model is frozen after release. |
128K | May 24, 2025 |
A Vertex AI Search model based on the The model is frozen after release. |
128K | May 24, 2025 |
gemini-1.5-flash-001/answer_gen/v2 |
A Vertex AI Search model based on the The model is frozen after release. |
128K | May 24, 2025 | Not Available | ||
gemini-1.5-flash-002/answer_gen/v1 |
A Vertex AI Search model based on the The model is frozen after release. |
128K | Sept 24, 2025 | Not Available | ||
text-bison@002/answer_gen/v1 |
A Vertex AI Search model based on the The model is frozen after release. |
8K | October 9, 2024 | Not Available | ||
medlm-medium/answer_gen/v1 |
Not Available | MedLM models have been trained on large-scale publicly available web information, public datasets and de-identified licenced private datasets with health and medical information. | 32k | November 16, 2024 | ||
preview |
The preview model specification points to the latest gemini-1.5-pro-002 model. The preview model is subject to change without notification. If you use this model, you might see changes in the responses when the model changes. If you want more consistency in the responses, select a specific model. |
128K | N/A | medlm-medium/answer_gen/v1 |
32k | N/A |