docs: Add documentation on how to contribute a Vector DB provider and

updated Test documentation and added a shortcut

Signed-off-by: Francisco Javier Arceo <farceo@redhat.com>

README.md

@@ -1,5 +1,8 @@
 # Llama Stack
 
+<a href="https://trendshift.io/repositories/11824" target="_blank"><img src="https://trendshift.io/api/badge/repositories/11824" alt="meta-llama%2Fllama-stack | Trendshift" style="width: 250px; height: 55px;" width="250" height="55"/></a>
+
+-----
 [![PyPI version](https://img.shields.io/pypi/v/llama_stack.svg)](https://pypi.org/project/llama_stack/)
 [![PyPI - Downloads](https://img.shields.io/pypi/dm/llama-stack)](https://pypi.org/project/llama-stack/)
 [![License](https://img.shields.io/pypi/l/llama_stack.svg)](https://github.com/meta-llama/llama-stack/blob/main/LICENSE)
@@ -9,6 +12,7 @@
 
 [**Quick Start**](https://llama-stack.readthedocs.io/en/latest/getting_started/index.html) | [**Documentation**](https://llama-stack.readthedocs.io/en/latest/index.html) | [**Colab Notebook**](./docs/getting_started.ipynb) | [**Discord**](https://discord.gg/llama-stack)
 
+
 ### ✨🎉 Llama 4 Support  🎉✨
 We released [Version 0.2.0](https://github.com/meta-llama/llama-stack/releases/tag/v0.2.0) with support for the Llama 4 herd of models released by Meta.
 
@@ -179,3 +183,17 @@ Please checkout our [Documentation](https://llama-stack.readthedocs.io/en/latest
 Check out our client SDKs for connecting to a Llama Stack server in your preferred language, you can choose from [python](https://github.com/meta-llama/llama-stack-client-python), [typescript](https://github.com/meta-llama/llama-stack-client-typescript), [swift](https://github.com/meta-llama/llama-stack-client-swift), and [kotlin](https://github.com/meta-llama/llama-stack-client-kotlin) programming languages to quickly build your applications.
 
 You can find more example scripts with client SDKs to talk with the Llama Stack server in our [llama-stack-apps](https://github.com/meta-llama/llama-stack-apps/tree/main/examples) repo.
+
+
+## 🌟 GitHub Star History
+## Star History
+
+[![Star History Chart](https://api.star-history.com/svg?repos=meta-llama/llama-stack&type=Date)](https://www.star-history.com/#meta-llama/llama-stack&Date)
+
+## ✨ Contributors
+
+Thanks to all of our amazing contributors!
+
+<a href="https://github.com/meta-llama/llama-stack/graphs/contributors">
+  <img src="https://contrib.rocks/image?repo=meta-llama/llama-stack" />
+</a>

docs/_static/js/keyboard_shortcuts.js

@@ -0,0 +1,14 @@
+document.addEventListener('keydown', function(event) {
+  // command+K or ctrl+K
+  if ((event.metaKey || event.ctrlKey) && event.key === 'k') {
+    event.preventDefault();
+    document.querySelector('.search-input, .search-field, input[name="q"]').focus();
+  }
+
+  // forward slash
+  if (event.key === '/' &&
+      !event.target.matches('input, textarea, select')) {
+    event.preventDefault();
+    document.querySelector('.search-input, .search-field, input[name="q"]').focus();
+  }
+});

docs/source/conf.py

@@ -131,6 +131,7 @@ html_static_path = ["../_static"]
 def setup(app):
     app.add_css_file("css/my_theme.css")
     app.add_js_file("js/detect_theme.js")
+    app.add_js_file("js/keyboard_shortcuts.js")
 
     def dockerhub_role(name, rawtext, text, lineno, inliner, options={}, content=[]):
         url = f"https://hub.docker.com/r/llamastack/{text}"

docs/source/contributing/index.md

@@ -2,14 +2,28 @@
 ```{include} ../../../CONTRIBUTING.md
 ```
 
-See the [Adding a New API Provider](new_api_provider.md) which describes how to add new API providers to the Stack.
+## Testing
 
+See the [Test Page](testing.md) which describes how to test your changes.
+```{toctree}
+:maxdepth: 1
+:hidden:
+:caption: Testing
 
+testing
+```
 
+## Adding a New Provider
+
+See the [Adding a New API Provider Page](new_api_provider.md) which describes how to add new API providers to the Stack.
+
+See the [Vector Database Page](new_vector_database.md) which describes how to add a new vector databases with Llama Stack.
+
+See the [External Provider Page](../providers/external/index.md) which describes how to add external providers to the Stack.
 ```{toctree}
 :maxdepth: 1
 :hidden:
 
 new_api_provider
-testing
+new_vector_database
 ```

docs/source/contributing/new_vector_database.md

@@ -0,0 +1,75 @@
+# Adding a New Vector Database
+
+This guide will walk you through the process of adding a new vector database to Llama Stack.
+
+> **_NOTE:_** Here's an example Pull Request of the [Milvus Vector Database Provider](https://github.com/meta-llama/llama-stack/pull/1467).
+
+Vector Database providers are used to store and retrieve vector embeddings. Vector databases are not limited to vector
+search but can support keyword and hybrid search. Additionally, vector database can also support operations like
+filtering, sorting, and aggregating vectors.
+
+## Steps to Add a New Vector Database Provider
+1. **Choose the Database Type**: Determine if your vector database is a remote service, inline, or both.
+   - Remote databases make requests to external services, while inline databases execute locally. Some providers support both.
+2. **Implement the Provider**: Create a new provider class that inherits from `VectorDatabaseProvider` and implements the required methods.
+   - Implement methods for vector storage, retrieval, search, and any additional features your database supports.
+     - You will need to implement the following methods for `YourVectorIndex`:
+        - `YourVectorIndex.create()`
+        - `YourVectorIndex.initialize()`
+        - `YourVectorIndex.add_chunks()`
+        - `YourVectorIndex.delete_chunk()`
+        - `YourVectorIndex.query_vector()`
+        - `YourVectorIndex.query_keyword()`
+        - `YourVectorIndex.query_hybrid()`
+     - You will need to implement the following methods for `YourVectorIOAdapter`:
+        - `YourVectorIOAdapter.initialize()`
+        - `YourVectorIOAdapter.shutdown()`
+        - `YourVectorIOAdapter.list_vector_dbs()`
+        - `YourVectorIOAdapter.register_vector_db()`
+        - `YourVectorIOAdapter.unregister_vector_db()`
+        - `YourVectorIOAdapter.insert_chunks()`
+        - `YourVectorIOAdapter.query_chunks()`
+        - `YourVectorIOAdapter.delete_chunks()`
+3. **Add to Registry**: Register your provider in the appropriate registry file.
+   - Update {repopath}`llama_stack/providers/registry/vector_io.py` to include your new provider.
+```python
+from llama_stack.providers.registry.specs import InlineProviderSpec
+from llama_stack.providers.registry.api import Api
+
+InlineProviderSpec(
+    api=Api.vector_io,
+    provider_type="inline::milvus",
+    pip_packages=["pymilvus>=2.4.10"],
+    module="llama_stack.providers.inline.vector_io.milvus",
+    config_class="llama_stack.providers.inline.vector_io.milvus.MilvusVectorIOConfig",
+    api_dependencies=[Api.inference],
+    optional_api_dependencies=[Api.files],
+    description="",
+),
+```
+4. **Add Tests**: Create unit tests and integration tests for your provider in the `tests/` directory.
+   - Unit Tests
+     - By following the structure of the class methods, you will be able to easily run unit and integration tests for your database.
+       1. You have to configure the tests for your provide in `/tests/unit/providers/vector_io/conftest.py`.
+       2. Update the `vector_provider` fixture to include your provider if they are an inline provider.
+       3. Create a `your_vectorprovider_index` fixture that initializes your vector index.
+       4. Create a `your_vectorprovider_adapter` fixture that initializes your vector adapter.
+       5. Add your provider to the `vector_io_providers` fixture dictionary.
+         - Please follow the naming convention of `your_vectorprovider_index` and `your_vectorprovider_adapter` as the tests require this to execute properly.
+   - Integration Tests
+     - Integration tests are located in {repopath}`tests/integration`. These tests use the python client-SDK APIs (from the `llama_stack_client` package) to test functionality.
+     - The two set of integration tests are:
+       - `tests/integration/vector_io/test_vector_io.py`: This file tests registration, insertion, and retrieval.
+       - `tests/integration/vector_io/test_openai_vector_stores.py`: These tests are for OpenAI-compatible vector stores and test the OpenAI API compatibility.
+        - You will need to update `skip_if_provider_doesnt_support_openai_vector_stores` to include your provider as well as `skip_if_provider_doesnt_support_openai_vector_stores_search` to test the appropriate search functionality.
+     - Running the tests in the GitHub CI
+       - You will need to update the `.github/workflows/integration-vector-io-tests.yml` file to include your provider.
+        - If your provider is a remote provider, you will also have to add a container to spin up and run it in the action.
+   - Updating the pyproject.yml
+     - If you are adding tests for the `inline` provider you will have to update the `unit` group.
+       - `uv add new_pip_package --group unit`
+     - If you are adding tests for the `remote` provider you will have to update the `test` group, which is used in the GitHub CI for integration tests.
+       - `uv add new_pip_package --group test`
+5. **Update Documentation**: Please update the documentation for end users
+   - Generate the provider documentation by running {repopath}`./scripts/provider_codegen.py`.
+   - Update the autogenerated content in the registry/vector_io.py file with information about your provider. Please see other providers for examples.

docs/source/contributing/testing.md

@@ -1,6 +1,8 @@
-# Testing Llama Stack
+```{include} ../../../tests/README.md
+```
 
-Tests are of three different kinds:
-- Unit tests
-- Provider focused integration tests
-- Client SDK tests
+```{include} ../../../tests/unit/README.md
+```
+
+```{include} ../../../tests/integration/README.md
+```

docs/source/providers/inference/index.md

@@ -29,6 +29,7 @@ remote_runpod
 remote_sambanova
 remote_tgi
 remote_together
+remote_vertexai
 remote_vllm
 remote_watsonx
 ```

docs/source/providers/inference/remote_vertexai.md

@@ -0,0 +1,40 @@
+# remote::vertexai
+
+## Description
+
+Google Vertex AI inference provider enables you to use Google's Gemini models through Google Cloud's Vertex AI platform, providing several advantages:
+
+• Enterprise-grade security: Uses Google Cloud's security controls and IAM
+• Better integration: Seamless integration with other Google Cloud services
+• Advanced features: Access to additional Vertex AI features like model tuning and monitoring
+• Authentication: Uses Google Cloud Application Default Credentials (ADC) instead of API keys
+
+Configuration:
+- Set VERTEX_AI_PROJECT environment variable (required)
+- Set VERTEX_AI_LOCATION environment variable (optional, defaults to us-central1)
+- Use Google Cloud Application Default Credentials or service account key
+
+Authentication Setup:
+Option 1 (Recommended): gcloud auth application-default login
+Option 2: Set GOOGLE_APPLICATION_CREDENTIALS to service account key path
+
+Available Models:
+- vertex_ai/gemini-2.0-flash
+- vertex_ai/gemini-2.5-flash
+- vertex_ai/gemini-2.5-pro
+
+## Configuration
+
+| Field | Type | Required | Default | Description |
+|-------|------|----------|---------|-------------|
+| `project` | `<class 'str'>` | No |  | Google Cloud project ID for Vertex AI |
+| `location` | `<class 'str'>` | No | us-central1 | Google Cloud location for Vertex AI |
+
+## Sample Configuration
+
+```yaml
+project: ${env.VERTEX_AI_PROJECT:=}
+location: ${env.VERTEX_AI_LOCATION:=us-central1}
+
+```
+

docs/source/providers/vector_io/inline_faiss.md

@@ -12,6 +12,18 @@ That means you'll get fast and efficient vector retrieval.
 - Lightweight and easy to use
 - Fully integrated with Llama Stack
 - GPU support
+- **Vector search** - FAISS supports pure vector similarity search using embeddings
+
+## Search Modes
+
+**Supported:**
+- **Vector Search** (`mode="vector"`): Performs vector similarity search using embeddings
+
+**Not Supported:**
+- **Keyword Search** (`mode="keyword"`): Not supported by FAISS
+- **Hybrid Search** (`mode="hybrid"`): Not supported by FAISS
+
+> **Note**: FAISS is designed as a pure vector similarity search library. See the [FAISS GitHub repository](https://github.com/facebookresearch/faiss) for more details about FAISS's core functionality.
 
 ## Usage
 

docs/source/providers/vector_io/remote_milvus.md

@@ -11,6 +11,7 @@ That means you're not limited to storing vectors in memory or in a separate serv
 
 - Easy to use
 - Fully integrated with Llama Stack
+- Supports all search modes: vector, keyword, and hybrid search (both inline and remote configurations)
 
 ## Usage
 
@@ -101,6 +102,92 @@ vector_io:
 - **`client_pem_path`**: Path to the **client certificate** file (required for mTLS).
 - **`client_key_path`**: Path to the **client private key** file (required for mTLS).
 
+## Search Modes
+
+Milvus supports three different search modes for both inline and remote configurations:
+
+### Vector Search
+Vector search uses semantic similarity to find the most relevant chunks based on embedding vectors. This is the default search mode and works well for finding conceptually similar content.
+
+```python
+# Vector search example
+search_response = client.vector_stores.search(
+    vector_store_id=vector_store.id,
+    query="What is machine learning?",
+    search_mode="vector",
+    max_num_results=5,
+)
+```
+
+### Keyword Search
+Keyword search uses traditional text-based matching to find chunks containing specific terms or phrases. This is useful when you need exact term matches.
+
+```python
+# Keyword search example
+search_response = client.vector_stores.search(
+    vector_store_id=vector_store.id,
+    query="Python programming language",
+    search_mode="keyword",
+    max_num_results=5,
+)
+```
+
+### Hybrid Search
+Hybrid search combines both vector and keyword search methods to provide more comprehensive results. It leverages the strengths of both semantic similarity and exact term matching.
+
+#### Basic Hybrid Search
+```python
+# Basic hybrid search example (uses RRF ranker with default impact_factor=60.0)
+search_response = client.vector_stores.search(
+    vector_store_id=vector_store.id,
+    query="neural networks in Python",
+    search_mode="hybrid",
+    max_num_results=5,
+)
+```
+
+**Note**: The default `impact_factor` value of 60.0 was empirically determined to be optimal in the original RRF research paper: ["Reciprocal Rank Fusion outperforms Condorcet and individual Rank Learning Methods"](https://plg.uwaterloo.ca/~gvcormac/cormacksigir09-rrf.pdf) (Cormack et al., 2009).
+
+#### Hybrid Search with RRF (Reciprocal Rank Fusion) Ranker
+RRF combines rankings from vector and keyword search by using reciprocal ranks. The impact factor controls how much weight is given to higher-ranked results.
+
+```python
+# Hybrid search with custom RRF parameters
+search_response = client.vector_stores.search(
+    vector_store_id=vector_store.id,
+    query="neural networks in Python",
+    search_mode="hybrid",
+    max_num_results=5,
+    ranking_options={
+        "ranker": {
+            "type": "rrf",
+            "impact_factor": 100.0,  # Higher values give more weight to top-ranked results
+        }
+    },
+)
+```
+
+#### Hybrid Search with Weighted Ranker
+Weighted ranker linearly combines normalized scores from vector and keyword search. The alpha parameter controls the balance between the two search methods.
+
+```python
+# Hybrid search with weighted ranker
+search_response = client.vector_stores.search(
+    vector_store_id=vector_store.id,
+    query="neural networks in Python",
+    search_mode="hybrid",
+    max_num_results=5,
+    ranking_options={
+        "ranker": {
+            "type": "weighted",
+            "alpha": 0.7,  # 70% vector search, 30% keyword search
+        }
+    },
+)
+```
+
+For detailed documentation on RRF and Weighted rankers, please refer to the [Milvus Reranking Guide](https://milvus.io/docs/reranking.md).
+
 ## Documentation
 See the [Milvus documentation](https://milvus.io/docs/install-overview.md) for more details about Milvus in general.
 

llama_stack/core/routing_tables/toolgroups.py

@@ -124,10 +124,7 @@ class ToolGroupsRoutingTable(CommonRoutingTableImpl, ToolGroups):
         return toolgroup
 
     async def unregister_toolgroup(self, toolgroup_id: str) -> None:
-        tool_group = await self.get_tool_group(toolgroup_id)
-        if tool_group is None:
-            raise ToolGroupNotFoundError(toolgroup_id)
-        await self.unregister_object(tool_group)
+        await self.unregister_object(await self.get_tool_group(toolgroup_id))
 
     async def shutdown(self) -> None:
         pass

llama_stack/distributions/ci-tests/build.yaml

@@ -14,6 +14,7 @@ distribution_spec:
     - provider_type: remote::openai
     - provider_type: remote::anthropic
     - provider_type: remote::gemini
+    - provider_type: remote::vertexai
     - provider_type: remote::groq
     - provider_type: remote::sambanova
     - provider_type: inline::sentence-transformers

llama_stack/distributions/ci-tests/run.yaml

@@ -65,6 +65,11 @@ providers:
     provider_type: remote::gemini
     config:
       api_key: ${env.GEMINI_API_KEY:=}
+  - provider_id: ${env.VERTEX_AI_PROJECT:+vertexai}
+    provider_type: remote::vertexai
+    config:
+      project: ${env.VERTEX_AI_PROJECT:=}
+      location: ${env.VERTEX_AI_LOCATION:=us-central1}
   - provider_id: groq
     provider_type: remote::groq
     config:

llama_stack/distributions/starter/build.yaml

@@ -14,6 +14,7 @@ distribution_spec:
     - provider_type: remote::openai
     - provider_type: remote::anthropic
     - provider_type: remote::gemini
+    - provider_type: remote::vertexai
     - provider_type: remote::groq
     - provider_type: remote::sambanova
     - provider_type: inline::sentence-transformers

llama_stack/distributions/starter/run.yaml

@@ -65,6 +65,11 @@ providers:
     provider_type: remote::gemini
     config:
       api_key: ${env.GEMINI_API_KEY:=}
+  - provider_id: ${env.VERTEX_AI_PROJECT:+vertexai}
+    provider_type: remote::vertexai
+    config:
+      project: ${env.VERTEX_AI_PROJECT:=}
+      location: ${env.VERTEX_AI_LOCATION:=us-central1}
   - provider_id: groq
     provider_type: remote::groq
     config:

llama_stack/distributions/starter/starter.py

@@ -56,6 +56,7 @@ ENABLED_INFERENCE_PROVIDERS = [
     "fireworks",
     "together",
     "gemini",
+    "vertexai",
     "groq",
     "sambanova",
     "anthropic",
@@ -71,6 +72,7 @@ INFERENCE_PROVIDER_IDS = {
     "tgi": "${env.TGI_URL:+tgi}",
     "cerebras": "${env.CEREBRAS_API_KEY:+cerebras}",
     "nvidia": "${env.NVIDIA_API_KEY:+nvidia}",
+    "vertexai": "${env.VERTEX_AI_PROJECT:+vertexai}",
 }
 
 
@@ -246,6 +248,14 @@ def get_distribution_template() -> DistributionTemplate:
                 "",
                 "Gemini API Key",
             ),
+            "VERTEX_AI_PROJECT": (
+                "",
+                "Google Cloud Project ID for Vertex AI",
+            ),
+            "VERTEX_AI_LOCATION": (
+                "us-central1",
+                "Google Cloud Location for Vertex AI",
+            ),
             "SAMBANOVA_API_KEY": (
                 "",
                 "SambaNova API Key",

llama_stack/providers/inline/vector_io/faiss/faiss.py

@@ -174,7 +174,9 @@ class FaissIndex(EmbeddingIndex):
         k: int,
         score_threshold: float,
     ) -> QueryChunksResponse:
-        raise NotImplementedError("Keyword search is not supported in FAISS")
+        raise NotImplementedError(
+            "Keyword search is not supported - underlying DB FAISS does not support this search mode"
+        )
 
     async def query_hybrid(
         self,
@@ -185,7 +187,9 @@ class FaissIndex(EmbeddingIndex):
         reranker_type: str,
         reranker_params: dict[str, Any] | None = None,
     ) -> QueryChunksResponse:
-        raise NotImplementedError("Hybrid search is not supported in FAISS")
+        raise NotImplementedError(
+            "Hybrid search is not supported - underlying DB FAISS does not support this search mode"
+        )
 
 
 class FaissVectorIOAdapter(OpenAIVectorStoreMixin, VectorIO, VectorDBsProtocolPrivate):

llama_stack/providers/registry/inference.py

@@ -213,6 +213,36 @@ def available_providers() -> list[ProviderSpec]:
                 description="Google Gemini inference provider for accessing Gemini models and Google's AI services.",
             ),
         ),
+        remote_provider_spec(
+            api=Api.inference,
+            adapter=AdapterSpec(
+                adapter_type="vertexai",
+                pip_packages=["litellm", "google-cloud-aiplatform"],
+                module="llama_stack.providers.remote.inference.vertexai",
+                config_class="llama_stack.providers.remote.inference.vertexai.VertexAIConfig",
+                provider_data_validator="llama_stack.providers.remote.inference.vertexai.config.VertexAIProviderDataValidator",
+                description="""Google Vertex AI inference provider enables you to use Google's Gemini models through Google Cloud's Vertex AI platform, providing several advantages:
+
+• Enterprise-grade security: Uses Google Cloud's security controls and IAM
+• Better integration: Seamless integration with other Google Cloud services
+• Advanced features: Access to additional Vertex AI features like model tuning and monitoring
+• Authentication: Uses Google Cloud Application Default Credentials (ADC) instead of API keys
+
+Configuration:
+- Set VERTEX_AI_PROJECT environment variable (required)
+- Set VERTEX_AI_LOCATION environment variable (optional, defaults to us-central1)
+- Use Google Cloud Application Default Credentials or service account key
+
+Authentication Setup:
+Option 1 (Recommended): gcloud auth application-default login
+Option 2: Set GOOGLE_APPLICATION_CREDENTIALS to service account key path
+
+Available Models:
+- vertex_ai/gemini-2.0-flash
+- vertex_ai/gemini-2.5-flash
+- vertex_ai/gemini-2.5-pro""",
+            ),
+        ),
         remote_provider_spec(
             api=Api.inference,
             adapter=AdapterSpec(

llama_stack/providers/registry/vector_io.py

@@ -45,6 +45,18 @@ That means you'll get fast and efficient vector retrieval.
 - Lightweight and easy to use
 - Fully integrated with Llama Stack
 - GPU support
+- **Vector search** - FAISS supports pure vector similarity search using embeddings
+
+## Search Modes
+
+**Supported:**
+- **Vector Search** (`mode="vector"`): Performs vector similarity search using embeddings
+
+**Not Supported:**
+- **Keyword Search** (`mode="keyword"`): Not supported by FAISS
+- **Hybrid Search** (`mode="hybrid"`): Not supported by FAISS
+
+> **Note**: FAISS is designed as a pure vector similarity search library. See the [FAISS GitHub repository](https://github.com/facebookresearch/faiss) for more details about FAISS's core functionality.
 
 ## Usage
 
@@ -535,6 +547,7 @@ That means you're not limited to storing vectors in memory or in a separate serv
 
 - Easy to use
 - Fully integrated with Llama Stack
+- Supports all search modes: vector, keyword, and hybrid search (both inline and remote configurations)
 
 ## Usage
 
@@ -625,6 +638,92 @@ vector_io:
 - **`client_pem_path`**: Path to the **client certificate** file (required for mTLS).
 - **`client_key_path`**: Path to the **client private key** file (required for mTLS).
 
+## Search Modes
+
+Milvus supports three different search modes for both inline and remote configurations:
+
+### Vector Search
+Vector search uses semantic similarity to find the most relevant chunks based on embedding vectors. This is the default search mode and works well for finding conceptually similar content.
+
+```python
+# Vector search example
+search_response = client.vector_stores.search(
+    vector_store_id=vector_store.id,
+    query="What is machine learning?",
+    search_mode="vector",
+    max_num_results=5,
+)
+```
+
+### Keyword Search
+Keyword search uses traditional text-based matching to find chunks containing specific terms or phrases. This is useful when you need exact term matches.
+
+```python
+# Keyword search example
+search_response = client.vector_stores.search(
+    vector_store_id=vector_store.id,
+    query="Python programming language",
+    search_mode="keyword",
+    max_num_results=5,
+)
+```
+
+### Hybrid Search
+Hybrid search combines both vector and keyword search methods to provide more comprehensive results. It leverages the strengths of both semantic similarity and exact term matching.
+
+#### Basic Hybrid Search
+```python
+# Basic hybrid search example (uses RRF ranker with default impact_factor=60.0)
+search_response = client.vector_stores.search(
+    vector_store_id=vector_store.id,
+    query="neural networks in Python",
+    search_mode="hybrid",
+    max_num_results=5,
+)
+```
+
+**Note**: The default `impact_factor` value of 60.0 was empirically determined to be optimal in the original RRF research paper: ["Reciprocal Rank Fusion outperforms Condorcet and individual Rank Learning Methods"](https://plg.uwaterloo.ca/~gvcormac/cormacksigir09-rrf.pdf) (Cormack et al., 2009).
+
+#### Hybrid Search with RRF (Reciprocal Rank Fusion) Ranker
+RRF combines rankings from vector and keyword search by using reciprocal ranks. The impact factor controls how much weight is given to higher-ranked results.
+
+```python
+# Hybrid search with custom RRF parameters
+search_response = client.vector_stores.search(
+    vector_store_id=vector_store.id,
+    query="neural networks in Python",
+    search_mode="hybrid",
+    max_num_results=5,
+    ranking_options={
+        "ranker": {
+            "type": "rrf",
+            "impact_factor": 100.0,  # Higher values give more weight to top-ranked results
+        }
+    },
+)
+```
+
+#### Hybrid Search with Weighted Ranker
+Weighted ranker linearly combines normalized scores from vector and keyword search. The alpha parameter controls the balance between the two search methods.
+
+```python
+# Hybrid search with weighted ranker
+search_response = client.vector_stores.search(
+    vector_store_id=vector_store.id,
+    query="neural networks in Python",
+    search_mode="hybrid",
+    max_num_results=5,
+    ranking_options={
+        "ranker": {
+            "type": "weighted",
+            "alpha": 0.7,  # 70% vector search, 30% keyword search
+        }
+    },
+)
+```
+
+For detailed documentation on RRF and Weighted rankers, please refer to the [Milvus Reranking Guide](https://milvus.io/docs/reranking.md).
+
 ## Documentation
 See the [Milvus documentation](https://milvus.io/docs/install-overview.md) for more details about Milvus in general.
 

llama_stack/providers/remote/inference/vertexai/__init__.py

@@ -0,0 +1,15 @@
+# Copyright (c) Meta Platforms, Inc. and affiliates.
+# All rights reserved.
+#
+# This source code is licensed under the terms described in the LICENSE file in
+# the root directory of this source tree.
+
+from .config import VertexAIConfig
+
+
+async def get_adapter_impl(config: VertexAIConfig, _deps):
+    from .vertexai import VertexAIInferenceAdapter
+
+    impl = VertexAIInferenceAdapter(config)
+    await impl.initialize()
+    return impl

llama_stack/providers/remote/inference/vertexai/config.py

@@ -0,0 +1,45 @@
+# Copyright (c) Meta Platforms, Inc. and affiliates.
+# All rights reserved.
+#
+# This source code is licensed under the terms described in the LICENSE file in
+# the root directory of this source tree.
+
+from typing import Any
+
+from pydantic import BaseModel, Field
+
+from llama_stack.schema_utils import json_schema_type
+
+
+class VertexAIProviderDataValidator(BaseModel):
+    vertex_project: str | None = Field(
+        default=None,
+        description="Google Cloud project ID for Vertex AI",
+    )
+    vertex_location: str | None = Field(
+        default=None,
+        description="Google Cloud location for Vertex AI (e.g., us-central1)",
+    )
+
+
+@json_schema_type
+class VertexAIConfig(BaseModel):
+    project: str = Field(
+        description="Google Cloud project ID for Vertex AI",
+    )
+    location: str = Field(
+        default="us-central1",
+        description="Google Cloud location for Vertex AI",
+    )
+
+    @classmethod
+    def sample_run_config(
+        cls,
+        project: str = "${env.VERTEX_AI_PROJECT:=}",
+        location: str = "${env.VERTEX_AI_LOCATION:=us-central1}",
+        **kwargs,
+    ) -> dict[str, Any]:
+        return {
+            "project": project,
+            "location": location,
+        }

llama_stack/providers/remote/inference/vertexai/models.py

@@ -0,0 +1,20 @@
+# Copyright (c) Meta Platforms, Inc. and affiliates.
+# All rights reserved.
+#
+# This source code is licensed under the terms described in the LICENSE file in
+# the root directory of this source tree.
+
+from llama_stack.providers.utils.inference.model_registry import (
+    ProviderModelEntry,
+)
+
+# Vertex AI model IDs with vertex_ai/ prefix as required by litellm
+LLM_MODEL_IDS = [
+    "vertex_ai/gemini-2.0-flash",
+    "vertex_ai/gemini-2.5-flash",
+    "vertex_ai/gemini-2.5-pro",
+]
+
+SAFETY_MODELS_ENTRIES = list[ProviderModelEntry]()
+
+MODEL_ENTRIES = [ProviderModelEntry(provider_model_id=m) for m in LLM_MODEL_IDS] + SAFETY_MODELS_ENTRIES

llama_stack/providers/remote/inference/vertexai/vertexai.py

@@ -0,0 +1,52 @@
+# Copyright (c) Meta Platforms, Inc. and affiliates.
+# All rights reserved.
+#
+# This source code is licensed under the terms described in the LICENSE file in
+# the root directory of this source tree.
+
+from typing import Any
+
+from llama_stack.apis.inference import ChatCompletionRequest
+from llama_stack.providers.utils.inference.litellm_openai_mixin import (
+    LiteLLMOpenAIMixin,
+)
+
+from .config import VertexAIConfig
+from .models import MODEL_ENTRIES
+
+
+class VertexAIInferenceAdapter(LiteLLMOpenAIMixin):
+    def __init__(self, config: VertexAIConfig) -> None:
+        LiteLLMOpenAIMixin.__init__(
+            self,
+            MODEL_ENTRIES,
+            litellm_provider_name="vertex_ai",
+            api_key_from_config=None,  # Vertex AI uses ADC, not API keys
+            provider_data_api_key_field="vertex_project",  # Use project for validation
+        )
+        self.config = config
+
+    def get_api_key(self) -> str:
+        # Vertex AI doesn't use API keys, it uses Application Default Credentials
+        # Return empty string to let litellm handle authentication via ADC
+        return ""
+
+    async def _get_params(self, request: ChatCompletionRequest) -> dict[str, Any]:
+        # Get base parameters from parent
+        params = await super()._get_params(request)
+
+        # Add Vertex AI specific parameters
+        provider_data = self.get_request_provider_data()
+        if provider_data:
+            if getattr(provider_data, "vertex_project", None):
+                params["vertex_project"] = provider_data.vertex_project
+            if getattr(provider_data, "vertex_location", None):
+                params["vertex_location"] = provider_data.vertex_location
+        else:
+            params["vertex_project"] = self.config.project
+            params["vertex_location"] = self.config.location
+
+        # Remove api_key since Vertex AI uses ADC
+        params.pop("api_key", None)
+
+        return params

tests/integration/inference/test_openai_completion.py

@@ -34,6 +34,7 @@ def skip_if_model_doesnt_support_openai_completion(client_with_models, model_id)
         "remote::runpod",
         "remote::sambanova",
         "remote::tgi",
+        "remote::vertexai",
     ):
         pytest.skip(f"Model {model_id} hosted by {provider.provider_type} doesn't support OpenAI completions.")
 

tests/integration/inference/test_text_inference.py

@@ -29,6 +29,7 @@ def skip_if_model_doesnt_support_completion(client_with_models, model_id):
             "remote::openai",
             "remote::anthropic",
             "remote::gemini",
+            "remote::vertexai",
             "remote::groq",
             "remote::sambanova",
         )