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Vertex AI RAG Engine, a component of the Vertex AI
Platform, facilitates Retrieval-Augmented Generation (RAG).
Vertex AI RAG Engine is also a data framework for developing
context-augmented large language model (LLM) applications. Context augmentation
occurs when you apply an LLM to your data. This implements retrieval-augmented
generation (RAG).
A common problem with LLMs is that they don't understand private knowledge, that
is, your organization's data. With Vertex AI RAG Engine, you can
enrich the LLM context with additional private information, because the model
can reduce hallucination and answer questions more accurately.
By combining additional knowledge sources with the existing knowledge that LLMs
have, a better context is provided. The improved context along with the query
enhances the quality of the LLM's response.
The following image illustrates the key concepts to understanding
Vertex AI RAG Engine.
These concepts are listed in the order of the retrieval-augmented generation
(RAG) process.
Data ingestion: Intake data from different data sources. For example,
local files, Cloud Storage, and Google Drive.
Data transformation:
Conversion of the data in preparation for indexing. For example, data is
split into chunks.
Embedding: Numerical
representations of words or pieces of text. These numbers capture the
semantic meaning and context of the text. Similar or related words or text
tend to have similar embeddings, which means they are closer together in the
high-dimensional vector space.
Data indexing: Vertex AI RAG Engine creates an index called a corpus.
The index structures the knowledge base so it's optimized for searching. For
example, the index is like a detailed table of contents for a massive
reference book.
Retrieval: When a user asks a question or provides a prompt, the retrieval
component in Vertex AI RAG Engine searches through its knowledge
base to find information that is relevant to the query.
Generation: The retrieved information becomes the context added to the
original user query as a guide for the generative AI model to generate
factually grounded and relevant responses.
Supported regions
Vertex AI RAG Engine is supported in the following regions:
Region
Location
Description
Launch stage
us-central1
Iowa
v1 and v1beta1 versions are supported.
Allowlist
us-east4
Virginia
v1 and v1beta1 versions are supported.
GA
europe-west3
Frankfurt, Germany
v1 and v1beta1 versions are supported.
GA
europe-west4
Eemshaven, Netherlands
v1 and v1beta1 versions are supported.
GA
us-central1 is changed to Allowlist. If you'd like to experiment with
Vertex AI RAG Engine, try other regions. If you plan to onboard
your production traffic to us-central1, contact vertex-ai-rag-engine-support@google.com.
[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Hard to understand","hardToUnderstand","thumb-down"],["Incorrect information or sample code","incorrectInformationOrSampleCode","thumb-down"],["Missing the information/samples I need","missingTheInformationSamplesINeed","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-08-26 UTC."],[],[],null,["| The [VPC-SC security controls](/vertex-ai/generative-ai/docs/security-controls) and\n| CMEK are supported by Vertex AI RAG Engine. Data residency and AXT security controls aren't\n| supported.\n| You must be added to the allowlist to access\n| Vertex AI RAG Engine in `us-central1`. For users\n| with existing projects, there is no impact. For users with new projects, you\n| can try other regions, or contact\n| `vertex-ai-rag-engine-support@google.com` to onboard to\n| `us-central1`.\n\nThis page describes what Vertex AI RAG Engine is and how it\nworks.\n\n| **Description** | **Console** |\n|-------------------------------------------------------------------------------------------------------------------------------------------------------------|----------------------------------------------------------------------------|\n| To learn how to use the Vertex AI SDK to run Vertex AI RAG Engine tasks, see the [RAG quickstart for Python](/vertex-ai/generative-ai/docs/rag-quickstart). | [Try Vertex AI RAG Engine](https://console.cloud.google.com/vertex-ai/rag) |\n\nOverview\n\nVertex AI RAG Engine, a component of the Vertex AI\nPlatform, facilitates Retrieval-Augmented Generation (RAG).\nVertex AI RAG Engine is also a data framework for developing\ncontext-augmented large language model (LLM) applications. Context augmentation\noccurs when you apply an LLM to your data. This implements retrieval-augmented\ngeneration (RAG).\n\nA common problem with LLMs is that they don't understand private knowledge, that\nis, your organization's data. With Vertex AI RAG Engine, you can\nenrich the LLM context with additional private information, because the model\ncan reduce hallucination and answer questions more accurately.\n\nBy combining additional knowledge sources with the existing knowledge that LLMs\nhave, a better context is provided. The improved context along with the query\nenhances the quality of the LLM's response.\n\nThe following image illustrates the key concepts to understanding\nVertex AI RAG Engine.\n\nThese concepts are listed in the order of the retrieval-augmented generation\n(RAG) process.\n\n1. **Data ingestion**: Intake data from different data sources. For example,\n local files, Cloud Storage, and Google Drive.\n\n2. [**Data transformation**](/vertex-ai/generative-ai/docs/fine-tune-rag-transformations):\n Conversion of the data in preparation for indexing. For example, data is\n split into chunks.\n\n3. [**Embedding**](/vertex-ai/generative-ai/docs/embeddings/get-text-embeddings): Numerical\n representations of words or pieces of text. These numbers capture the\n semantic meaning and context of the text. Similar or related words or text\n tend to have similar embeddings, which means they are closer together in the\n high-dimensional vector space.\n\n4. **Data indexing** : Vertex AI RAG Engine creates an index called a [corpus](/vertex-ai/generative-ai/docs/manage-your-rag-corpus#corpus-management).\n The index structures the knowledge base so it's optimized for searching. For\n example, the index is like a detailed table of contents for a massive\n reference book.\n\n5. **Retrieval**: When a user asks a question or provides a prompt, the retrieval\n component in Vertex AI RAG Engine searches through its knowledge\n base to find information that is relevant to the query.\n\n6. **Generation** : The retrieved information becomes the context added to the\n original user query as a guide for the generative AI model to generate\n factually [grounded](/vertex-ai/generative-ai/docs/grounding/overview) and relevant responses.\n\nSupported regions\n\nVertex AI RAG Engine is supported in the following regions:\n\n| Region | Location | Description | Launch stage |\n|----------------|------------------------|--------------------------------------------|--------------|\n| `us-central1` | Iowa | `v1` and `v1beta1` versions are supported. | Allowlist |\n| `us-east4` | Virginia | `v1` and `v1beta1` versions are supported. | GA |\n| `europe-west3` | Frankfurt, Germany | `v1` and `v1beta1` versions are supported. | GA |\n| `europe-west4` | Eemshaven, Netherlands | `v1` and `v1beta1` versions are supported. | GA |\n\n- `us-central1` is changed to `Allowlist`. If you'd like to experiment with Vertex AI RAG Engine, try other regions. If you plan to onboard your production traffic to `us-central1`, contact `vertex-ai-rag-engine-support@google.com`.\n\nSubmit feedback\n\nTo chat with Google support, go to the [Vertex AI RAG Engine\nsupport\ngroup](https://groups.google.com/a/google.com/g/vertex-ai-rag-engine-support).\n\nTo send an email, use the email address\n`vertex-ai-rag-engine-support@google.com`.\n\nWhat's next\n\n- To learn how to use the Vertex AI SDK to run Vertex AI RAG Engine tasks, see [RAG quickstart for\n Python](/vertex-ai/generative-ai/docs/rag-quickstart).\n- To learn about grounding, see [Grounding\n overview](/vertex-ai/generative-ai/docs/grounding/overview).\n- To learn more about the responses from RAG, see [Retrieval and Generation Output of Vertex AI RAG Engine](/vertex-ai/generative-ai/docs/model-reference/rag-output-explained).\n- To learn about the RAG architecture:\n - [Infrastructure for a RAG-capable generative AI application using Vertex AI and Vector Search](/architecture/gen-ai-rag-vertex-ai-vector-search)\n - [Infrastructure for a RAG-capable generative AI application using Vertex AI and AlloyDB for PostgreSQL](/architecture/rag-capable-gen-ai-app-using-vertex-ai)."]]