Python: Feature/azure ai search agentic rag (search as separate package) (#2328)

* Python: Fix pyright errors and move search provider to core (#1546)

* address pablo coments

* update azure ai search pypi version to latest prev

* init update

* Fix MyPy type annotation errors in search provider

- Add type annotation to DEFAULT_CONTEXT_PROMPT
- Add type annotation to vectorizable_fields
- Add union type annotation to vector_queries

* Fix DEFAULT_CONTEXT_PROMPT MyPy error and update test

- Rename DEFAULT_CONTEXT_PROMPT to _DEFAULT_SEARCH_CONTEXT_PROMPT to avoid conflict with base class Final variable
- Update test to use new constant name
- All core package tests passing (1123 passed)

* Python: Move Azure AI Search to separate package per PR feedback

Addresses reviewer feedback from PR #1546 by isolating the beta dependency
(azure-search-documents==11.7.0b2) into a new agent-framework-aisearch package.

Changes:
- Created new agent-framework-aisearch package with complete structure
- Moved AzureAISearchContextProvider from core to aisearch package
- Added AzureAISearchSettings class for environment variable auto-loading
- Added support for direct API key string (auto-converts to AzureKeyCredential)
- Added azure_openai_api_key parameter for Knowledge Base authentication
- Updated embedding_function type to Callable[[str], Awaitable[list[float]]]
- Moved Role import to top-level imports
- Maintained lazy loading through agent_framework.azure module
- Removed beta dependency from core package
- Updated all tests to use new package location
- All quality checks pass: ruff format/lint, pyright, mypy (0 errors)
- All 21 unit tests pass with 59% coverage

Semantic search mode verified working with both API key and managed identity authentication.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

* Python: Clarify top_k parameter only applies to semantic mode

Updated documentation to clarify that the top_k parameter only affects
semantic search mode. In agentic mode, the server-side Knowledge Base
determines retrieval based on query complexity and reasoning effort.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

* Python: Add Knowledge Base output mode and retrieval reasoning effort parameters

Added support for configurable Knowledge Base behavior in agentic mode:

- knowledge_base_output_mode: "extractive_data" (default) or "answer_synthesis"
  Some knowledge sources require answer_synthesis mode for proper functionality.

- retrieval_reasoning_effort: "minimal" (default), "medium", or "low"
  Controls query planning complexity and multi-hop reasoning depth.

These parameters give users fine-grained control over Knowledge Base behavior
and enable support for knowledge sources that require answer synthesis.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

* effort and outputmode query params

* Address PR review feedback for Azure AI Search context provider

* comments eduward

* ed latest comments

---------

Co-authored-by: Farzad Sunavala <farzad.sunavala.enovate.ai>
Co-authored-by: farzad528 <farzad528@users.noreply.github.com>
Co-authored-by: Claude <noreply@anthropic.com>
This commit is contained in:
Farzad Sunavala
2025-11-20 22:34:46 +00:00
committed by GitHub
Unverified
parent ab3d898979
commit 04e711cd55
14 changed files with 2330 additions and 0 deletions
@@ -0,0 +1,16 @@
# Copyright (c) Microsoft. All rights reserved.
import importlib.metadata
from ._search_provider import AzureAISearchContextProvider, AzureAISearchSettings
try:
__version__ = importlib.metadata.version(__name__)
except importlib.metadata.PackageNotFoundError:
__version__ = "0.0.0" # Fallback for development mode
__all__ = [
"AzureAISearchContextProvider",
"AzureAISearchSettings",
"__version__",
]
@@ -0,0 +1,914 @@
# Copyright (c) Microsoft. All rights reserved.
"""Azure AI Search Context Provider for Agent Framework.
This module provides context providers for Azure AI Search integration with two modes:
- Agentic: Recommended for most scenarios. Uses Knowledge Bases for query planning and
multi-hop reasoning. Slightly slower with more token consumption, but more accurate.
- Semantic: Fast hybrid search (vector + keyword) with semantic ranker. Best for simple
queries where speed is critical.
See: https://techcommunity.microsoft.com/blog/azure-ai-foundry-blog/foundry-iq-boost-response-relevance-by-36-with-agentic-retrieval/4470720
"""
import sys
from collections.abc import Awaitable, Callable, MutableSequence
from typing import TYPE_CHECKING, Any, ClassVar, Literal
from agent_framework import ChatMessage, Context, ContextProvider, Role
from agent_framework._logging import get_logger
from agent_framework._pydantic import AFBaseSettings
from agent_framework.exceptions import ServiceInitializationError
from azure.core.credentials import AzureKeyCredential
from azure.core.credentials_async import AsyncTokenCredential
from azure.core.exceptions import ResourceNotFoundError
from azure.search.documents.aio import SearchClient
from azure.search.documents.indexes.aio import SearchIndexClient
from azure.search.documents.indexes.models import (
AzureOpenAIVectorizerParameters,
KnowledgeBase,
KnowledgeBaseAzureOpenAIModel,
KnowledgeRetrievalLowReasoningEffort,
KnowledgeRetrievalMediumReasoningEffort,
KnowledgeRetrievalMinimalReasoningEffort,
KnowledgeRetrievalOutputMode,
KnowledgeRetrievalReasoningEffort,
KnowledgeSourceReference,
SearchIndexKnowledgeSource,
SearchIndexKnowledgeSourceParameters,
)
from azure.search.documents.models import (
QueryCaptionType,
QueryType,
VectorizableTextQuery,
VectorizedQuery,
)
from pydantic import SecretStr, ValidationError
# Type checking imports for optional agentic mode dependencies
if TYPE_CHECKING:
from azure.search.documents.knowledgebases.aio import KnowledgeBaseRetrievalClient
from azure.search.documents.knowledgebases.models import (
KnowledgeBaseMessage,
KnowledgeBaseMessageTextContent,
KnowledgeBaseRetrievalRequest,
KnowledgeRetrievalIntent,
KnowledgeRetrievalSemanticIntent,
)
from azure.search.documents.knowledgebases.models import (
KnowledgeRetrievalLowReasoningEffort as KBRetrievalLowReasoningEffort,
)
from azure.search.documents.knowledgebases.models import (
KnowledgeRetrievalMediumReasoningEffort as KBRetrievalMediumReasoningEffort,
)
from azure.search.documents.knowledgebases.models import (
KnowledgeRetrievalMinimalReasoningEffort as KBRetrievalMinimalReasoningEffort,
)
from azure.search.documents.knowledgebases.models import (
KnowledgeRetrievalOutputMode as KBRetrievalOutputMode,
)
from azure.search.documents.knowledgebases.models import (
KnowledgeRetrievalReasoningEffort as KBRetrievalReasoningEffort,
)
# Runtime imports for agentic mode (optional dependency)
try:
from azure.search.documents.knowledgebases.aio import KnowledgeBaseRetrievalClient
from azure.search.documents.knowledgebases.models import (
KnowledgeBaseMessage,
KnowledgeBaseMessageTextContent,
KnowledgeBaseRetrievalRequest,
KnowledgeRetrievalIntent,
KnowledgeRetrievalSemanticIntent,
)
from azure.search.documents.knowledgebases.models import (
KnowledgeRetrievalLowReasoningEffort as KBRetrievalLowReasoningEffort,
)
from azure.search.documents.knowledgebases.models import (
KnowledgeRetrievalMediumReasoningEffort as KBRetrievalMediumReasoningEffort,
)
from azure.search.documents.knowledgebases.models import (
KnowledgeRetrievalMinimalReasoningEffort as KBRetrievalMinimalReasoningEffort,
)
from azure.search.documents.knowledgebases.models import (
KnowledgeRetrievalOutputMode as KBRetrievalOutputMode,
)
from azure.search.documents.knowledgebases.models import (
KnowledgeRetrievalReasoningEffort as KBRetrievalReasoningEffort,
)
_agentic_retrieval_available = True
except ImportError:
_agentic_retrieval_available = False
if sys.version_info >= (3, 11):
from typing import Self # pragma: no cover
else:
from typing_extensions import Self # pragma: no cover
if sys.version_info >= (3, 12):
from typing import override # type: ignore # pragma: no cover
else:
from typing_extensions import override # type: ignore[import] # pragma: no cover
# Module-level constants
logger = get_logger("agent_framework.azure")
_DEFAULT_AGENTIC_MESSAGE_HISTORY_COUNT = 10
class AzureAISearchSettings(AFBaseSettings):
"""Settings for Azure AI Search Context Provider with auto-loading from environment.
The settings are first loaded from environment variables with the prefix 'AZURE_SEARCH_'.
If the environment variables are not found, the settings can be loaded from a .env file.
Keyword Args:
endpoint: Azure AI Search endpoint URL.
Can be set via environment variable AZURE_SEARCH_ENDPOINT.
index_name: Name of the search index.
Can be set via environment variable AZURE_SEARCH_INDEX_NAME.
api_key: API key for authentication (optional, use managed identity if not provided).
Can be set via environment variable AZURE_SEARCH_API_KEY.
env_file_path: If provided, the .env settings are read from this file path location.
env_file_encoding: The encoding of the .env file, defaults to 'utf-8'.
Examples:
.. code-block:: python
from agent_framework_aisearch import AzureAISearchSettings
# Using environment variables
# Set AZURE_SEARCH_ENDPOINT=https://mysearch.search.windows.net
# Set AZURE_SEARCH_INDEX_NAME=my-index
settings = AzureAISearchSettings()
# Or passing parameters directly
settings = AzureAISearchSettings(
endpoint="https://mysearch.search.windows.net",
index_name="my-index",
)
# Or loading from a .env file
settings = AzureAISearchSettings(env_file_path="path/to/.env")
"""
env_prefix: ClassVar[str] = "AZURE_SEARCH_"
endpoint: str | None = None
index_name: str | None = None
api_key: SecretStr | None = None
class AzureAISearchContextProvider(ContextProvider):
"""Azure AI Search Context Provider with hybrid search and semantic ranking.
This provider retrieves relevant documents from Azure AI Search to provide context
to the AI agent. It supports two modes:
- **agentic**: Recommended for most scenarios. Uses Knowledge Bases for query planning
and multi-hop reasoning. Slightly slower with more token consumption, but provides
more accurate results (up to 36% improvement in response relevance).
- **semantic** (default): Fast hybrid search combining vector and keyword search
with semantic reranking. Best for simple queries where speed is critical.
Examples:
Using environment variables (recommended):
.. code-block:: python
from agent_framework_aisearch import AzureAISearchContextProvider
from azure.identity.aio import DefaultAzureCredential
# Set AZURE_SEARCH_ENDPOINT and AZURE_SEARCH_INDEX_NAME in environment
search_provider = AzureAISearchContextProvider(credential=DefaultAzureCredential())
Semantic hybrid search with API key:
.. code-block:: python
# Direct API key string
search_provider = AzureAISearchContextProvider(
endpoint="https://mysearch.search.windows.net",
index_name="my-index",
api_key="my-api-key",
mode="semantic",
)
Loading from .env file:
.. code-block:: python
# Load settings from a .env file
search_provider = AzureAISearchContextProvider(
credential=DefaultAzureCredential(), env_file_path="path/to/.env"
)
Agentic retrieval for complex queries:
.. code-block:: python
# Use agentic mode for multi-hop reasoning
# Note: azure_openai_resource_url is the OpenAI endpoint for Knowledge Base model calls,
# which is different from azure_ai_project_endpoint (the AI Foundry project endpoint)
search_provider = AzureAISearchContextProvider(
endpoint="https://mysearch.search.windows.net",
index_name="my-index",
credential=DefaultAzureCredential(),
mode="agentic",
azure_openai_resource_url="https://myresource.openai.azure.com",
model_deployment_name="gpt-4o",
knowledge_base_name="my-knowledge-base",
)
"""
_DEFAULT_SEARCH_CONTEXT_PROMPT = "Use the following context to answer the question:"
def __init__(
self,
endpoint: str | None = None,
index_name: str | None = None,
api_key: str | AzureKeyCredential | None = None,
credential: AsyncTokenCredential | None = None,
*,
mode: Literal["semantic", "agentic"] = "semantic",
top_k: int = 5,
semantic_configuration_name: str | None = None,
vector_field_name: str | None = None,
embedding_function: Callable[[str], Awaitable[list[float]]] | None = None,
context_prompt: str | None = None,
# Agentic mode parameters (Knowledge Base)
azure_ai_project_endpoint: str | None = None,
azure_openai_resource_url: str | None = None,
model_deployment_name: str | None = None,
model_name: str | None = None,
knowledge_base_name: str | None = None,
retrieval_instructions: str | None = None,
azure_openai_api_key: str | None = None,
knowledge_base_output_mode: Literal["extractive_data", "answer_synthesis"] = "extractive_data",
retrieval_reasoning_effort: Literal["minimal", "medium", "low"] = "minimal",
agentic_message_history_count: int = _DEFAULT_AGENTIC_MESSAGE_HISTORY_COUNT,
env_file_path: str | None = None,
env_file_encoding: str | None = None,
) -> None:
"""Initialize Azure AI Search Context Provider.
Args:
endpoint: Azure AI Search endpoint URL.
Can also be set via environment variable AZURE_SEARCH_ENDPOINT.
index_name: Name of the search index to query.
Can also be set via environment variable AZURE_SEARCH_INDEX_NAME.
api_key: API key for authentication (string or AzureKeyCredential).
Can also be set via environment variable AZURE_SEARCH_API_KEY.
credential: AsyncTokenCredential for managed identity authentication.
Use this for Entra ID authentication instead of api_key.
mode: Search mode - "semantic" for hybrid search with semantic ranking (fast)
or "agentic" for multi-hop reasoning (slower). Default: "semantic".
top_k: Maximum number of documents to retrieve. Only applies to semantic mode.
In agentic mode, the server-side Knowledge Base determines retrieval based on
query complexity and reasoning effort. Default: 5.
semantic_configuration_name: Name of semantic configuration in the index.
Required for semantic ranking. If None, uses index default.
vector_field_name: Name of the vector field in the index for hybrid search.
Required if using vector search. Default: None (keyword search only).
embedding_function: Async function to generate embeddings for vector search.
Signature: async def embed(text: str) -> list[float]
Required if vector_field_name is specified and no server-side vectorization.
context_prompt: Custom prompt to prepend to retrieved context.
Default: "Use the following context to answer the question:"
azure_ai_project_endpoint: Azure AI Foundry project endpoint URL.
This is NOT the same as azure_openai_resource_url - the project endpoint is used
for Azure AI Foundry services, while the OpenAI endpoint is used by the Knowledge
Base to call the model for query planning. Required for agentic mode.
Example: "https://myproject.services.ai.azure.com/api/projects/myproject"
azure_openai_resource_url: Azure OpenAI resource URL for Knowledge Base model calls.
This is the OpenAI endpoint used by the Knowledge Base to call the LLM for
query planning and reasoning. This is separate from the project endpoint because
the Knowledge Base directly calls Azure OpenAI for its internal operations.
Required for agentic mode. Example: "https://myresource.openai.azure.com"
model_deployment_name: Model deployment name in Azure OpenAI for Knowledge Base.
This is the deployment name the Knowledge Base uses to call the LLM.
Required for agentic mode.
model_name: The underlying model name (e.g., "gpt-4o", "gpt-4o-mini").
If not provided, defaults to model_deployment_name. Used for Knowledge Base configuration.
knowledge_base_name: Name for the Knowledge Base. Required for agentic mode.
retrieval_instructions: Custom instructions for the Knowledge Base's
retrieval planning. Only used in agentic mode.
azure_openai_api_key: Azure OpenAI API key for Knowledge Base to call the model.
Only needed when using API key authentication instead of managed identity.
knowledge_base_output_mode: Output mode for Knowledge Base retrieval. Only used in agentic mode.
"extractive_data": Returns raw chunks without synthesis (default, recommended for agent integration).
"answer_synthesis": Returns synthesized answer from the LLM.
Some knowledge sources require answer_synthesis mode. Default: "extractive_data".
retrieval_reasoning_effort: Reasoning effort for Knowledge Base query planning. Only used in agentic mode.
"minimal": Fastest, basic query planning.
"medium": Moderate reasoning with some query decomposition.
"low": Lower reasoning effort than medium.
Default: "minimal".
agentic_message_history_count: Number of recent messages from conversation history to send to
the Knowledge Base. This context helps with query planning in agentic mode, allowing the
Knowledge Base to understand the conversation flow and generate better retrieval queries.
There is no technical limit - adjust based on your use case. Default: 10.
env_file_path: Path to environment file for loading settings.
env_file_encoding: Encoding of the environment file.
Examples:
.. code-block:: python
from agent_framework_aisearch import AzureAISearchContextProvider
from azure.identity.aio import DefaultAzureCredential
# Using environment variables
# Set AZURE_SEARCH_ENDPOINT=https://mysearch.search.windows.net
# Set AZURE_SEARCH_INDEX_NAME=my-index
credential = DefaultAzureCredential()
provider = AzureAISearchContextProvider(credential=credential)
# Or passing parameters directly
provider = AzureAISearchContextProvider(
endpoint="https://mysearch.search.windows.net",
index_name="my-index",
credential=credential,
)
# Or loading from a .env file
provider = AzureAISearchContextProvider(credential=credential, env_file_path="path/to/.env")
"""
# Load settings from environment/file
try:
settings = AzureAISearchSettings(
endpoint=endpoint,
index_name=index_name,
api_key=api_key if isinstance(api_key, str) else None,
env_file_path=env_file_path,
env_file_encoding=env_file_encoding,
)
except ValidationError as ex:
raise ServiceInitializationError("Failed to create Azure AI Search settings.", ex) from ex
# Validate required parameters
if not settings.endpoint:
raise ServiceInitializationError(
"Azure AI Search endpoint is required. Set via 'endpoint' parameter "
"or 'AZURE_SEARCH_ENDPOINT' environment variable."
)
if not settings.index_name:
raise ServiceInitializationError(
"Azure AI Search index name is required. Set via 'index_name' parameter "
"or 'AZURE_SEARCH_INDEX_NAME' environment variable."
)
# Determine the credential to use
resolved_credential: AzureKeyCredential | AsyncTokenCredential
if credential:
# AsyncTokenCredential takes precedence
resolved_credential = credential
elif isinstance(api_key, AzureKeyCredential):
resolved_credential = api_key
elif settings.api_key:
resolved_credential = AzureKeyCredential(settings.api_key.get_secret_value())
else:
raise ServiceInitializationError(
"Azure credential is required. Provide 'api_key' or 'credential' parameter "
"or set 'AZURE_SEARCH_API_KEY' environment variable."
)
self.endpoint = settings.endpoint
self.index_name = settings.index_name
self.credential = resolved_credential
self.mode = mode
self.top_k = top_k
self.semantic_configuration_name = semantic_configuration_name
self.vector_field_name = vector_field_name
self.embedding_function = embedding_function
self.context_prompt = context_prompt or self._DEFAULT_SEARCH_CONTEXT_PROMPT
# Agentic mode parameters (Knowledge Base)
self.azure_openai_resource_url = azure_openai_resource_url
self.azure_openai_deployment_name = model_deployment_name
# If model_name not provided, default to deployment name
self.model_name = model_name or model_deployment_name
self.knowledge_base_name = knowledge_base_name
self.retrieval_instructions = retrieval_instructions
self.azure_openai_api_key = azure_openai_api_key
self.azure_ai_project_endpoint = azure_ai_project_endpoint
self.knowledge_base_output_mode = knowledge_base_output_mode
self.retrieval_reasoning_effort = retrieval_reasoning_effort
self.agentic_message_history_count = agentic_message_history_count
# Auto-discover vector field if not specified
self._auto_discovered_vector_field = False
self._use_vectorizable_query = False # Will be set to True if server-side vectorization detected
if not vector_field_name and mode == "semantic":
# Attempt to auto-discover vector field from index schema
# This will be done lazily on first search to avoid blocking initialization
pass
# Validation
if vector_field_name and not embedding_function:
raise ValueError("embedding_function is required when vector_field_name is specified")
if mode == "agentic":
if not _agentic_retrieval_available:
raise ImportError(
"Agentic retrieval requires azure-search-documents >= 11.7.0b1 with Knowledge Base support. "
"Please upgrade: pip install azure-search-documents>=11.7.0b1"
)
if not self.azure_openai_resource_url:
raise ValueError(
"azure_openai_resource_url is required for agentic mode. "
"This should be your Azure OpenAI endpoint (e.g., 'https://myresource.openai.azure.com')"
)
if not self.azure_openai_deployment_name:
raise ValueError("model_deployment_name is required for agentic mode")
if not knowledge_base_name:
raise ValueError("knowledge_base_name is required for agentic mode")
# Create search client for semantic mode
self._search_client = SearchClient(
endpoint=self.endpoint,
index_name=self.index_name,
credential=self.credential,
)
# Create index client and retrieval client for agentic mode (Knowledge Base)
self._index_client: SearchIndexClient | None = None
self._retrieval_client: KnowledgeBaseRetrievalClient | None = None
if mode == "agentic":
self._index_client = SearchIndexClient(
endpoint=self.endpoint,
credential=self.credential,
)
# Retrieval client will be created after Knowledge Base initialization
self._knowledge_base_initialized = False
async def __aenter__(self) -> Self:
"""Async context manager entry."""
return self
async def __aexit__(
self,
exc_type: type[BaseException] | None,
exc_val: BaseException | None,
exc_tb: Any,
) -> None:
"""Async context manager exit - cleanup clients.
Args:
exc_type: Exception type if an error occurred.
exc_val: Exception value if an error occurred.
exc_tb: Exception traceback if an error occurred.
"""
# Close retrieval client if it was created
if self._retrieval_client is not None:
await self._retrieval_client.close()
self._retrieval_client = None
@override
async def invoking(
self,
messages: ChatMessage | MutableSequence[ChatMessage],
**kwargs: Any,
) -> Context:
"""Retrieve relevant context from Azure AI Search before model invocation.
Args:
messages: User messages to use for context retrieval.
**kwargs: Additional arguments (unused).
Returns:
Context object with retrieved documents as messages.
"""
# Convert to list and filter to USER/ASSISTANT messages with text only
messages_list = [messages] if isinstance(messages, ChatMessage) else list(messages)
filtered_messages = [
msg
for msg in messages_list
if msg and msg.text and msg.text.strip() and msg.role in [Role.USER, Role.ASSISTANT]
]
if not filtered_messages:
return Context()
# Perform search based on mode
if self.mode == "semantic":
# Semantic mode: flatten messages to single query
query = "\n".join(msg.text for msg in filtered_messages)
search_result_parts = await self._semantic_search(query)
else: # agentic
# Agentic mode: pass recent messages as conversation history
recent_messages = filtered_messages[-self.agentic_message_history_count :]
search_result_parts = await self._agentic_search(recent_messages)
# Format results as context - return multiple messages for each result part
if not search_result_parts:
return Context()
# Create context messages: first message with prompt, then one message per result part
context_messages = [ChatMessage(role=Role.USER, text=self.context_prompt)]
context_messages.extend([ChatMessage(role=Role.USER, text=part) for part in search_result_parts])
return Context(messages=context_messages)
def _find_vector_fields(self, index: Any) -> list[str]:
"""Find all fields that can store vectors (have dimensions defined).
Args:
index: SearchIndex object from Azure Search.
Returns:
List of vector field names.
"""
return [
field.name
for field in index.fields
if field.vector_search_dimensions is not None and field.vector_search_dimensions > 0
]
def _find_vectorizable_fields(self, index: Any, vector_fields: list[str]) -> list[str]:
"""Find vector fields that have auto-vectorization configured.
These are fields that have a vectorizer in their profile, meaning the index
can automatically vectorize text queries without needing a client-side embedding function.
Args:
index: SearchIndex object from Azure Search.
vector_fields: List of vector field names.
Returns:
List of vectorizable field names (subset of vector_fields).
"""
vectorizable_fields: list[str] = []
# Check if index has vector search configuration
if not index.vector_search or not index.vector_search.profiles:
return vectorizable_fields
# For each vector field, check if it has a vectorizer configured
for field in index.fields:
if field.name in vector_fields and field.vector_search_profile_name:
# Find the profile for this field
profile = next(
(p for p in index.vector_search.profiles if p.name == field.vector_search_profile_name), None
)
if profile and hasattr(profile, "vectorizer_name") and profile.vectorizer_name:
# This field has server-side vectorization configured
vectorizable_fields.append(field.name)
return vectorizable_fields
async def _auto_discover_vector_field(self) -> None:
"""Auto-discover vector field from index schema.
Attempts to find vector fields in the index and detect which have server-side
vectorization configured. Prioritizes vectorizable fields (which can auto-embed text)
over regular vector fields (which require client-side embedding).
"""
if self._auto_discovered_vector_field or self.vector_field_name:
return # Already discovered or manually specified
try:
# Use existing index client or create temporary one
if not self._index_client:
self._index_client = SearchIndexClient(endpoint=self.endpoint, credential=self.credential)
index_client = self._index_client
# Get index schema
index = await index_client.get_index(self.index_name)
# Step 1: Find all vector fields
vector_fields = self._find_vector_fields(index)
if not vector_fields:
# No vector fields found - keyword search only
logger.info(f"No vector fields found in index '{self.index_name}'. Using keyword-only search.")
self._auto_discovered_vector_field = True
return
# Step 2: Find which vector fields have server-side vectorization
vectorizable_fields = self._find_vectorizable_fields(index, vector_fields)
# Step 3: Decide which field to use
if vectorizable_fields:
# Prefer vectorizable fields (server-side embedding)
if len(vectorizable_fields) == 1:
self.vector_field_name = vectorizable_fields[0]
self._auto_discovered_vector_field = True
self._use_vectorizable_query = True # Use VectorizableTextQuery
logger.info(
f"Auto-discovered vectorizable field '{self.vector_field_name}' "
f"with server-side vectorization. No embedding_function needed."
)
else:
# Multiple vectorizable fields
logger.warning(
f"Multiple vectorizable fields found: {vectorizable_fields}. "
f"Please specify vector_field_name explicitly. Using keyword-only search."
)
elif len(vector_fields) == 1:
# Single vector field without vectorizer - needs client-side embedding
self.vector_field_name = vector_fields[0]
self._auto_discovered_vector_field = True
self._use_vectorizable_query = False
if not self.embedding_function:
logger.warning(
f"Auto-discovered vector field '{self.vector_field_name}' without server-side vectorization. "
f"Provide embedding_function for vector search, or it will fall back to keyword-only search."
)
self.vector_field_name = None
else:
# Multiple vector fields without vectorizers
logger.warning(
f"Multiple vector fields found: {vector_fields}. "
f"Please specify vector_field_name explicitly. Using keyword-only search."
)
except Exception as e:
# Log warning but continue with keyword search
logger.warning(f"Failed to auto-discover vector field: {e}. Using keyword-only search.")
self._auto_discovered_vector_field = True # Mark as attempted
async def _semantic_search(self, query: str) -> list[str]:
"""Perform semantic hybrid search with semantic ranking.
This is the recommended mode for most use cases. It combines:
- Vector search (if embedding_function provided)
- Keyword search (BM25)
- Semantic reranking (if semantic_configuration_name provided)
Args:
query: Search query text.
Returns:
List of formatted search result strings, one per document.
"""
# Auto-discover vector field if not already done
await self._auto_discover_vector_field()
vector_queries: list[VectorizableTextQuery | VectorizedQuery] = []
# Build vector query based on server-side vectorization or client-side embedding
if self.vector_field_name:
# Use larger k for vector query when semantic reranker is enabled for better ranking quality
vector_k = max(self.top_k, 50) if self.semantic_configuration_name else self.top_k
if self._use_vectorizable_query:
# Server-side vectorization: Index will auto-embed the text query
vector_queries = [
VectorizableTextQuery(
text=query,
k_nearest_neighbors=vector_k,
fields=self.vector_field_name,
)
]
elif self.embedding_function:
# Client-side embedding: We provide the vector
query_vector = await self.embedding_function(query)
vector_queries = [
VectorizedQuery(
vector=query_vector,
k_nearest_neighbors=vector_k,
fields=self.vector_field_name,
)
]
# else: vector_field_name is set but no vectorization available - skip vector search
# Build search parameters
search_params: dict[str, Any] = {
"search_text": query,
"top": self.top_k,
}
if vector_queries:
search_params["vector_queries"] = vector_queries
# Add semantic ranking if configured
if self.semantic_configuration_name:
search_params["query_type"] = QueryType.SEMANTIC
search_params["semantic_configuration_name"] = self.semantic_configuration_name
search_params["query_caption"] = QueryCaptionType.EXTRACTIVE
# Execute search
results = await self._search_client.search(**search_params) # type: ignore[reportUnknownVariableType]
# Format results with citations
formatted_results: list[str] = []
async for doc in results: # type: ignore[reportUnknownVariableType]
# Extract document ID for citation
doc_id = doc.get("id") or doc.get("@search.id") # type: ignore[reportUnknownVariableType]
# Use full document chunks with citation
doc_text: str = self._extract_document_text(doc, doc_id=doc_id) # type: ignore[reportUnknownArgumentType]
if doc_text:
formatted_results.append(doc_text) # type: ignore[reportUnknownArgumentType]
return formatted_results
async def _ensure_knowledge_base(self) -> None:
"""Ensure Knowledge Base and knowledge source are created.
This method is idempotent - it will only create resources if they don't exist.
Note: Azure SDK uses KnowledgeAgent classes internally, but the feature
is marketed as "Knowledge Bases" in Azure AI Search.
"""
if self._knowledge_base_initialized or not self._index_client:
return
# Runtime validation for agentic mode parameters
if not self.knowledge_base_name:
raise ValueError("knowledge_base_name is required for agentic mode")
if not self.azure_openai_resource_url:
raise ValueError("azure_openai_resource_url is required for agentic mode")
if not self.azure_openai_deployment_name:
raise ValueError("model_deployment_name is required for agentic mode")
knowledge_base_name = self.knowledge_base_name
# Step 1: Create or get knowledge source
knowledge_source_name = f"{self.index_name}-source"
try:
# Try to get existing knowledge source
await self._index_client.get_knowledge_source(knowledge_source_name)
except ResourceNotFoundError:
# Create new knowledge source if it doesn't exist
knowledge_source = SearchIndexKnowledgeSource(
name=knowledge_source_name,
description=f"Knowledge source for {self.index_name} search index",
search_index_parameters=SearchIndexKnowledgeSourceParameters(
search_index_name=self.index_name,
),
)
await self._index_client.create_knowledge_source(knowledge_source)
# Step 2: Create or update Knowledge Base
# Always create/update to ensure configuration is current
aoai_params = AzureOpenAIVectorizerParameters(
resource_url=self.azure_openai_resource_url,
deployment_name=self.azure_openai_deployment_name,
model_name=self.model_name,
api_key=self.azure_openai_api_key,
)
# Map output mode string to SDK enum
output_mode = (
KnowledgeRetrievalOutputMode.EXTRACTIVE_DATA
if self.knowledge_base_output_mode == "extractive_data"
else KnowledgeRetrievalOutputMode.ANSWER_SYNTHESIS
)
# Map reasoning effort string to SDK class
reasoning_effort_map: dict[str, KnowledgeRetrievalReasoningEffort] = {
"minimal": KnowledgeRetrievalMinimalReasoningEffort(),
"medium": KnowledgeRetrievalMediumReasoningEffort(),
"low": KnowledgeRetrievalLowReasoningEffort(),
}
reasoning_effort = reasoning_effort_map[self.retrieval_reasoning_effort]
knowledge_base = KnowledgeBase(
name=knowledge_base_name,
description=f"Knowledge Base for multi-hop retrieval across {self.index_name}",
knowledge_sources=[
KnowledgeSourceReference(
name=knowledge_source_name,
)
],
models=[KnowledgeBaseAzureOpenAIModel(azure_open_ai_parameters=aoai_params)],
output_mode=output_mode,
retrieval_reasoning_effort=reasoning_effort,
)
await self._index_client.create_or_update_knowledge_base(knowledge_base)
self._knowledge_base_initialized = True
# Create retrieval client now that Knowledge Base is initialized
if _agentic_retrieval_available and self._retrieval_client is None:
self._retrieval_client = KnowledgeBaseRetrievalClient(
endpoint=self.endpoint,
knowledge_base_name=knowledge_base_name,
credential=self.credential,
)
async def _agentic_search(self, messages: list[ChatMessage]) -> list[str]:
"""Perform agentic retrieval with multi-hop reasoning using Knowledge Bases.
This mode uses query planning and is slightly slower than semantic search,
but provides more accurate results through intelligent retrieval.
This method uses Azure AI Search Knowledge Bases which:
1. Analyze the query and plan sub-queries
2. Retrieve relevant documents across multiple sources
3. Perform multi-hop reasoning with an LLM
4. Synthesize a comprehensive answer with references
Args:
messages: Conversation history to use for retrieval context.
Returns:
List of answer parts from the Knowledge Base, one per content item.
"""
# Ensure Knowledge Base is initialized
await self._ensure_knowledge_base()
# Map reasoning effort string to SDK class (for retrieval requests)
reasoning_effort_map: dict[str, KBRetrievalReasoningEffort] = {
"minimal": KBRetrievalMinimalReasoningEffort(),
"medium": KBRetrievalMediumReasoningEffort(),
"low": KBRetrievalLowReasoningEffort(),
}
reasoning_effort = reasoning_effort_map[self.retrieval_reasoning_effort]
# Map output mode string to SDK enum (for retrieval requests)
output_mode = (
KBRetrievalOutputMode.EXTRACTIVE_DATA
if self.knowledge_base_output_mode == "extractive_data"
else KBRetrievalOutputMode.ANSWER_SYNTHESIS
)
# For minimal reasoning, use intents API; for medium/low, use messages API
if self.retrieval_reasoning_effort == "minimal":
# Minimal reasoning uses intents with a single search query
query = "\n".join(msg.text for msg in messages if msg.text)
intents: list[KnowledgeRetrievalIntent] = [KnowledgeRetrievalSemanticIntent(search=query)]
retrieval_request = KnowledgeBaseRetrievalRequest(
intents=intents,
retrieval_reasoning_effort=reasoning_effort,
output_mode=output_mode,
include_activity=True,
)
else:
# Medium/low reasoning uses messages with conversation history
kb_messages = [
KnowledgeBaseMessage(
role=msg.role.value if hasattr(msg.role, "value") else str(msg.role),
content=[KnowledgeBaseMessageTextContent(text=msg.text)],
)
for msg in messages
if msg.text
]
retrieval_request = KnowledgeBaseRetrievalRequest(
messages=kb_messages,
retrieval_reasoning_effort=reasoning_effort,
output_mode=output_mode,
include_activity=True,
)
# Use reusable retrieval client
if not self._retrieval_client:
raise RuntimeError("Retrieval client not initialized. Ensure Knowledge Base is set up correctly.")
# Perform retrieval via Knowledge Base
retrieval_result = await self._retrieval_client.retrieve(retrieval_request=retrieval_request)
# Extract answer parts from response
if retrieval_result.response and len(retrieval_result.response) > 0:
# Get the assistant's response (last message)
assistant_message = retrieval_result.response[-1]
if assistant_message.content:
# Extract all text content items as separate parts
answer_parts: list[str] = []
for content_item in assistant_message.content:
# Check if this is a text content item
if isinstance(content_item, KnowledgeBaseMessageTextContent) and content_item.text:
answer_parts.append(content_item.text)
if answer_parts:
return answer_parts
# Fallback if no answer generated
return ["No results found from Knowledge Base."]
def _extract_document_text(self, doc: dict[str, Any], doc_id: str | None = None) -> str:
"""Extract readable text from a search document with optional citation.
Args:
doc: Search result document.
doc_id: Optional document ID for citation.
Returns:
Formatted document text with citation if doc_id provided.
"""
# Try common text field names
text = ""
for field in ["content", "text", "description", "body", "chunk"]:
if doc.get(field):
text = str(doc[field])
break
# Fallback: concatenate all string fields
if not text:
text_parts: list[str] = []
for key, value in doc.items():
if isinstance(value, str) and not key.startswith("@") and key != "id":
text_parts.append(f"{key}: {value}")
text = " | ".join(text_parts) if text_parts else ""
# Add citation if document ID provided
if doc_id and text:
return f"[Source: {doc_id}] {text}"
return text