agent-rag

Agent Retrieval Augmented Generation (RAG)

Microsoft Agent Framework supports adding Retrieval Augmented Generation (RAG) capabilities to agents easily by adding AI Context Providers to the agent.

::: zone pivot="programming-language-csharp"

Using TextSearchProvider

The TextSearchProvider class is an out-of-the-box implementation of a RAG context provider.

It can easily be attached to a ChatClientAgent using the AIContextProviderFactory option to provide RAG capabilities to the agent.

The factory is an async function that receives a context object and a cancellation token.

// Create the AI agent with the TextSearchProvider as the AI context provider.
AIAgent agent = azureOpenAIClient
    .GetChatClient(deploymentName)
    .AsAIAgent(new ChatClientAgentOptions
    {
        ChatOptions = new() { Instructions = "You are a helpful support specialist for Contoso Outdoors. Answer questions using the provided context and cite the source document when available." },
        AIContextProviderFactory = (ctx, ct) => new ValueTask<AIContextProvider>(
            new TextSearchProvider(SearchAdapter, ctx.SerializedState, ctx.JsonSerializerOptions, textSearchOptions))
    });

The TextSearchProvider requires a function that provides the search results given a query. This can be implemented using any search technology, e.g. Azure AI Search, or a web search engine.

Here is an example of a mock search function that returns pre-defined results based on the query. SourceName and SourceLink are optional, but if provided will be used by the agent to cite the source of the information when answering the user's question.

static Task<IEnumerable<TextSearchProvider.TextSearchResult>> SearchAdapter(string query, CancellationToken cancellationToken)
{
    // The mock search inspects the user's question and returns pre-defined snippets
    // that resemble documents stored in an external knowledge source.
    List<TextSearchProvider.TextSearchResult> results = new();

    if (query.Contains("return", StringComparison.OrdinalIgnoreCase) || query.Contains("refund", StringComparison.OrdinalIgnoreCase))
    {
        results.Add(new()
        {
            SourceName = "Contoso Outdoors Return Policy",
            SourceLink = "https://contoso.com/policies/returns",
            Text = "Customers may return any item within 30 days of delivery. Items should be unused and include original packaging. Refunds are issued to the original payment method within 5 business days of inspection."
        });
    }

    return Task.FromResult<IEnumerable<TextSearchProvider.TextSearchResult>>(results);
}