agent-framework/python/samples/02-agents/context_providers/azure_ai_search

Azure AI Search Context Provider Examples

Azure AI Search context provider enables Retrieval Augmented Generation (RAG) with your agents by retrieving relevant documents from Azure AI Search indexes. It supports two search modes optimized for different use cases.

This folder contains examples demonstrating how to use the Azure AI Search context provider with the Agent Framework.

Examples

File	Description
search_context_agentic.py	Agentic mode (recommended for most scenarios): Uses Knowledge Bases in Azure AI Search for query planning and multi-hop reasoning. Provides more accurate results through intelligent retrieval with automatic query reformulation. Slightly slower with more token consumption for query planning. Learn more
search_context_semantic.py	Semantic mode (fast queries): Fast hybrid search combining vector and keyword search with semantic ranking. Returns raw search results as context. Best for scenarios where speed is critical and simple retrieval is sufficient.

Installation

pip install agent-framework-foundry-search agent-framework-foundry

Prerequisites

Required Resources

1. Azure AI Search service with a search index containing your documents

   • Create Azure AI Search service
   • Create and populate a search index

2. Azure AI Foundry project with a model deployment

   • Create Azure AI Foundry project
   • Deploy a model (e.g., GPT-4o)

3. For Agentic mode only: Azure OpenAI resource for Knowledge Base model calls

   • Create Azure OpenAI resource
   • Note: This is separate from your Azure AI Foundry project endpoint

Authentication

Both examples support two authentication methods:

• API Key: Set AZURE_SEARCH_API_KEY environment variable
• Entra ID (Managed Identity): Uses DefaultAzureCredential when API key is not provided

Run az login if using Entra ID authentication.

Configuration

Environment Variables

Common (both modes):

• AZURE_SEARCH_ENDPOINT: Your Azure AI Search endpoint (e.g., https://myservice.search.windows.net)
• AZURE_SEARCH_INDEX_NAME: Name of your search index
• AZURE_AI_PROJECT_ENDPOINT: Your Azure AI Foundry project endpoint
• AZURE_AI_MODEL_DEPLOYMENT_NAME: Model deployment name (e.g., gpt-4o, defaults to gpt-4o)
• AZURE_SEARCH_API_KEY: (Optional) Your search API key - if not provided, uses DefaultAzureCredential

Agentic mode only:

• AZURE_SEARCH_KNOWLEDGE_BASE_NAME: Name of your Knowledge Base in Azure AI Search
• AZURE_OPENAI_RESOURCE_URL: Your Azure OpenAI resource URL (e.g., https://myresource.openai.azure.com)
  • Important: This is different from AZURE_AI_PROJECT_ENDPOINT - Knowledge Base needs the OpenAI endpoint for model calls

Example .env file

For Semantic Mode:

AZURE_SEARCH_ENDPOINT=https://myservice.search.windows.net
AZURE_SEARCH_INDEX_NAME=my-index
AZURE_AI_PROJECT_ENDPOINT=https://<resource-name>.services.ai.azure.com/api/projects/<project-name>
AZURE_AI_MODEL_DEPLOYMENT_NAME=gpt-4o
# Optional - omit to use Entra ID
AZURE_SEARCH_API_KEY=your-search-key

For Agentic Mode (add these to semantic mode variables):

AZURE_SEARCH_KNOWLEDGE_BASE_NAME=my-knowledge-base
AZURE_OPENAI_RESOURCE_URL=https://myresource.openai.azure.com

Search Modes Comparison

Feature	Semantic Mode	Agentic Mode
Speed	Fast	Slower (query planning overhead)
Token Usage	Lower	Higher (query reformulation)
Retrieval Strategy	Hybrid search + semantic ranking	Multi-hop reasoning with Knowledge Base
Query Handling	Direct search	Automatic query reformulation
Best For	Simple queries, speed-critical apps	Complex queries, multi-document reasoning
Additional Setup	None	Requires Knowledge Base + OpenAI resource

When to Use Semantic Mode

• Simple queries where direct keyword/vector search is sufficient
• Speed is critical and you need low latency
• Straightforward retrieval from single documents
• Lower token costs are important

When to Use Agentic Mode

• Complex queries requiring multi-hop reasoning
• Cross-document analysis where information spans multiple sources
• Ambiguous queries that benefit from automatic reformulation
• Higher accuracy is more important than speed
• You need intelligent query planning and document synthesis

How the Examples Work

Semantic Mode Flow

1. User query is sent to Azure AI Search
2. Hybrid search (vector + keyword) retrieves relevant documents
3. Semantic ranking reorders results for relevance
4. Top-k documents are returned as context
5. Agent generates response using retrieved context

Agentic Mode Flow

1. User query is sent to the Knowledge Base
2. Knowledge Base plans the retrieval strategy
3. Multiple search queries may be executed (multi-hop)
4. Retrieved information is synthesized
5. Enhanced context is provided to the agent
6. Agent generates response with comprehensive context

Code Example

Semantic Mode

from agent_framework import Agent
from agent_framework.azure import AzureAIAgentClient, AzureAISearchContextProvider
from azure.identity.aio import DefaultAzureCredential

# Create search provider with semantic mode (default)
search_provider = AzureAISearchContextProvider(
    endpoint=search_endpoint,
    index_name=index_name,
    api_key=search_key,  # Or use credential for Entra ID
    mode="semantic",  # Default mode
    top_k=3,  # Number of documents to retrieve
)

# Create agent with search context
async with AzureAIAgentClient(credential=DefaultAzureCredential()) as client:
    async with Agent(
        client=client,
        model=model_deployment,
        context_providers=[search_provider],
    ) as agent:
        response = await agent.run("What information is in the knowledge base?")

Agentic Mode

from agent_framework.azure import AzureAISearchContextProvider

# Create search provider with agentic mode
search_provider = AzureAISearchContextProvider(
    endpoint=search_endpoint,
    index_name=index_name,
    api_key=search_key,
    mode="agentic",  # Enable agentic retrieval
    knowledge_base_name=knowledge_base_name,
    azure_openai_resource_url=azure_openai_resource_url,
    top_k=5,
)

# Use with agent (same as semantic mode)
async with Agent(
    client=client,
    model=model_deployment,
    context_providers=[search_provider],
) as agent:
    response = await agent.run("Analyze and compare topics across documents")

Running the Examples

1. Set up environment variables (see Configuration section above)

2. Ensure you have an Azure AI Search index with documents:

   # Verify your index exists
   curl -X GET "https://myservice.search.windows.net/indexes/my-index?api-version=2024-07-01" \
        -H "api-key: YOUR_API_KEY"
   

3. For agentic mode: Create a Knowledge Base in Azure AI Search

   • Knowledge Base documentation

4. Run the examples:

   # Semantic mode (fast, simple)
   python azure_ai_with_search_context_semantic.py
   
   # Agentic mode (intelligent, complex)
   python azure_ai_with_search_context_agentic.py
   

Key Parameters

Common Parameters

• endpoint: Azure AI Search service endpoint
• index_name: Name of the search index
• api_key: API key for authentication (optional, can use credential instead)
• credential: Azure credential for Entra ID auth (e.g., DefaultAzureCredential())
• mode: Search mode - "semantic" (default) or "agentic"
• top_k: Number of documents to retrieve (default: 3 for semantic, 5 for agentic)

Semantic Mode Parameters

• semantic_configuration: Name of semantic configuration in your index (optional)
• query_type: Query type - "semantic" for semantic search (default)

Agentic Mode Parameters

• knowledge_base_name: Name of your Knowledge Base (required)
• azure_openai_resource_url: Azure OpenAI resource URL (required)
• max_search_queries: Maximum number of search queries to generate (default: 3)

Troubleshooting

Common Issues

1. Authentication errors

   • Ensure AZURE_SEARCH_API_KEY is set, or run az login for Entra ID auth
   • Verify your credentials have search permissions

2. Index not found

   • Verify AZURE_SEARCH_INDEX_NAME matches your index name exactly
   • Check that the index exists and contains documents

3. Agentic mode errors

   • Ensure AZURE_SEARCH_KNOWLEDGE_BASE_NAME is correctly configured
   • Verify AZURE_OPENAI_RESOURCE_URL points to your Azure OpenAI resource (not AI Foundry endpoint)
   • Check that your OpenAI resource has the necessary model deployments

4. No results returned

   • Verify your index has documents with vector embeddings (for semantic/hybrid search)
   • Check that your queries match the content in your index
   • Try increasing top_k parameter

5. Slow responses in agentic mode

   • This is expected - agentic mode trades speed for accuracy
   • Reduce max_search_queries if needed
   • Consider semantic mode for speed-critical applications

Performance Tips

• Use semantic mode as the default for most scenarios - it's fast and effective
• Switch to agentic mode when you need multi-hop reasoning or complex queries
• Adjust top_k based on your needs - higher values provide more context but increase token usage
• Enable semantic configuration in your index for better semantic ranking
• Use Entra ID authentication in production for better security

Additional Resources

• Azure AI Search Documentation
• Azure AI Foundry Documentation
• RAG with Azure AI Search
• Semantic Search in Azure AI Search
• Knowledge Bases in Azure AI Search
• Agentic Retrieval Blog Post