Knowledge Base and Tools
How a voice agent answers questions. Covers the knowledge-base lookup it inherits from its linked VEX chatbot, the workflow tools and context tools it can call, and how to tell whether a question needs a tool or a direct answer.
One Brain, Two Mouths
A voice agent never has its own knowledge base. It always borrows the knowledge base of the VEX chatbot it is linked to. Anything Vex can answer on chat, the voice agent can answer on the phone, in the same wording style, with the same source articles.
What the Agent Can Call
Linking a VEX gives the voice agent access to three tool categories — the same three Vex uses on chat:
Knowledge-base lookup
Searches the linked KB articles, FAQs, scraped URLs and uploaded documents. This is the default for almost every factual question.
Workflow tools
Custom tools you've defined on the chatbot — fetching live data (account status, order details), creating tickets, sending emails, triggering an external API.
Context tools
Built-in tools that read context the agent already has — caller's phone number, current call duration, business hours, the agent's own configuration.
When the Agent Uses a Tool
Gemini Live decides per turn whether to answer directly or call a tool. In practice:
- Generic factual question ("what are your shipping zones?") → KB lookup.
- Personal/account question ("where is my order?") → workflow tool that takes the order number.
- Procedural decision ("are you open right now?") → context tool to check current business hours.
- Small-talk or known-from-prompt ("are you a robot?") → direct answer, no tool.
The agent will say things like "let me check that for you" when it needs a beat to call a tool. That latency is normal and intended — it gives the caller a cue that the agent is doing real work rather than hallucinating.