Q&A Node
Overview
The Q&A node allows your Virtual Assistant (VA) to access the Indexes you have created in the Knowledge AI tab and generate accurate, context-aware answers based on your content. Instead of relying on predefined intents and entities, it uses your uploaded materials, known as Sources, to dynamically respond to user inquiries. Responses are generated using the Knowledge AI RAG (Retrieval-Augmented Generation) pipeline, which combines Vonage's proprietary Semantic Search with Google Gemini's large language models (LLMs).

Prerequisties
Knowledge AI tab configured
The Knowledge AI tab must be set up with at least one Index before you configure the Q&A node. For setup instructions, see Knowledge AI.
Limitations
Single Index per node
Each Q&A node is restricted to one Index.
Single VA per Index
Indexes are scoped to one VA per API key.
Single-turn processing
The Q&A node processes one input and returns one output. It does not support back-and-forth conversation.
Non-deterministic answer length
Exact control over response length is not guaranteed due to the non-deterministic nature of the LLMs used by Knowledge AI.
Setting up the Q&A Node
To configure the Q&A node:
Select an Index
Choose one Index to serve as the knowledge base for that node. Only Indexes created under the API key for the selected VA that are not already in use by another VA appear in the dropdown. Each Q&A node supports one Index. To access different Sources across different parts of your flow, use multiple Q&A nodes and assign a different Index to each.
For more information, see the Group Your Sources to Create Indexes section on the Knowledge AI page.
Managing Indexes across multiple Q&A nodes and VAs
To handle different knowledge domains within the same VA, use multiple Q&A nodes and assign a different Index to each.
Indexes are restricted to one VA per API key. If you cannot find an Index in the dropdown, check whether it is already in use by another VA.
To use the same content across multiple VAs under the same API key, duplicate the Index and assign it to the other VA. For instructions, see the Duplicating an Index section on the Knowledge AI page.
Capture the output
Under the Output Parameter dropdown, select the parameter to store the generated answer. Pass this parameter into a Speak/Send Message or Collect Input node to deliver the response to the end user.
Expected processing delay
There may be a 2- to 5-second delay while the system processes the query and generates the response.
Exit paths
The Q&A node has four exit paths that determine how your VA flow continues after the node processes a user query.
Knowledge AI response
Knowledge AI successfully retrieves and returns a relevant answer from the knowledge base.
Don't Know
Knowledge AI cannot find a suitable answer in the knowledge base.
Failed
A runtime error occurs, or the waiting time is exceeded.
Clarification Required
Knowledge AI identifies that the user query requires additional context or clarification before a response can be generated. This path is triggered when the input is too ambiguous, incomplete, or brief to retrieve a relevant answer accurately.
Handling the Clarification Required path
When Knowledge AI detects that a query is too ambiguous to process, it triggers the Clarification Required exit path. Use this path to route the user to a follow-up prompt that requests more context. Once the user provides a more complete query, route the flow back to the Q&A node to process the refined input.
The following table shows examples of unclear or incomplete inputs and suggested VA follow-up questions:
"benefits"
"What is the company benefits policy?"
"What is your question about benefits?"
"work from home policy"
"What is the company's work-from-home policy?"
"Are you asking about eligibility, the application process, or equipment?"
"data privacy EU law"
"What does EU law say about data privacy?"
"Are you asking about GDPR requirements or data processing obligations?"
Configurations
Intelligent query prep (Optional)
The Intelligent query prep switch allows Knowledge AI to understand and respond to follow-up queries based on the ongoing conversation, without requiring the user to restate previous context. This setting is available in both the Q&A node and the Index Tester. To access it in the Index Tester, select the gear icon at the top-right corner of the interface.
Context handling
Enables contextual understanding for follow-up questions. Uses session conversation history to interpret meaning.
Each query is processed independently.
Latency
Adds 300 to 1000 ms as Knowledge AI retrieves and processes context.
No additional latency.
Responses when context is unavailable
N/A
May produce "I don't know" responses if context is required.
Recommended setting
Keep this switch ON for smoother, more human-like interactions.
Turn it OFF if each query is unrelated or if lower latency is required.
Always test your VA flows to understand how context affects accuracy and response time.
Answer length (Optional)
Use Answer length to control how detailed Knowledge AI's responses should be.
Choose whether the response should be:
Shorter: suitable for simple answers.
Longer: suitable for complex, context-heavy queries.
The minimum is 100 characters or 20 words, with no upper limit. This field is disabled when Output mode is set to Search.
Not defined
Knowledge AI automatically determines the best answer length based on the query and the knowledge base.
Defined
Knowledge AI treats the value as a soft constraint. The response will generally fall within a small range of the specified value.
Latency and accuracy trade-off
Longer answers increase accuracy but also increase latency. Exact control over response length is not guaranteed due to the non-deterministic nature of the LLMs used by Knowledge AI. Treat the Answer length value as a soft constraint and test your flows to find the setting that works best for your use case.
Response guidelines (Optional)
Response guidelines availability
The Response guidelines field is disabled in both the Q&A node and the Index Tester when Output mode is set to Search.
Use Response guidelines to set the tone, format, and scope of Knowledge AI responses with custom instructions.
Tone: formal, friendly, concise, and similar options.
Topic restrictions: prevent the assistant from responding to out-of-scope queries.
Custom guardrails: rules for responses based on testing feedback.
Company-specific terminology: ensure branding consistency. For example, use "Vonage" instead of "we".
These guidelines help align your assistant's voice with your brand and use case.
Single-turn processing
Knowledge AI operates in single-turn mode:
The Q&A node processes one input and returns one output.
After returning the response, the node is marked as completed.
It does not support back-and-forth conversation. To reuse the same Q&A node, add a loop in your VA flow.
For setup instructions, see Using the Q&A node in your VA flow.
Waiting time
Waiting time determines how long the VA waits for a response from Knowledge AI.
Default: 3 seconds
Configurable range: 2 to 10 seconds
Choosing the right waiting time
Shorter wait times feel more natural in human conversation.
Longer wait times reduce API timeout risk but may affect flow pacing, especially for voice channels.
Managing Outputs
The Output mode setting defines how Knowledge AI processes and returns information from your Knowledge Base.
There are two modes available:
Search & Respond.
Search.
What it returns
A single, refined text answer ready to send to the end user.
Raw text chunks retrieved from the knowledge base.
Typical output size
100 to 500 characters.
250 to 2500 characters per chunk.
Best for
Customer-facing conversational flows.
Passing retrieved content to another AI process or agent
Answer length and Response guidelines fields
Available
Disabled
Search & Respond
Search & Respond is the default output mode. Knowledge AI searches your knowledge base, passes the retrieved content to an LLM, and returns a single concise answer directly to the end user. Use this mode when you want Knowledge AI to handle both retrieval and response generation automatically.
Output characteristics:
Responses are typically 100 to 500 characters long.
Answers are short, structured, and optimized for clarity.
Best suited for customer-facing conversational use cases.
Search
Search mode retrieves the most relevant text chunks from your knowledge base without generating a summarized response. The raw content is returned for further processing by another AI process, workflow, or agent. Use this mode when Knowledge AI acts as a tool within an AI Agent, or when minimising latency is a priority.
Output characteristics:
The output consists of multiple text chunks, typically ranging from 250 to 2500 characters each.
The raw text may include long passages or multiple paragraphs.
It is not recommended to send this output directly to end users.
Disabled fields in Search mode
When Output mode is set to Search, the Answer length and Response guidelines fields are disabled in both the Q&A node and the Index Tester.
Diagnosing Knowledge AI outputs
If Knowledge AI returns incomplete or incorrect answers, check its behavior manually using AI Studio Reports or the upcoming Knowledge AI Insights.
The following table describes common issues and recommended actions:
Ambiguous user question
Query is unclear or incomplete.
Ask the user to clarify or rephrase within the VA flow.
Outside Knowledge Base scope
The Index lacks relevant data.
Add new, relevant material to the Knowledge Base.
Search issue
Information exists but is not being retrieved.
Review and optimize source formatting.
Partial or inaccurate answer
Model retrieved but misunderstood content.
Improve Source structure or revise Response Guidelines.
Using the Q&A Node in your VA
The Q&A node is most effective when used as part of a broader conversational setup. The following are common patterns:
Collect Input node, then Q&A node, then return result.
Use as a fallback if other nodes fail.
Route back to the Q&A node after collecting more context.
Context not retained between uses
The Q&A node does not retain previous answers. Add context before sending the query if needed.
You can also use the Context Switch node to allow the VA to pivot between topics.
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