Tools
Tools are actions your Vio agent can call in the middle of a conversation — looking up an order, creating a ticket, checking availability, or booking a demo — and then speaking the result back to the caller. You build tools once in the Tools view, then enable only the ones each agent needs from that agent’s Tools tab.
The three kinds of tool
Custom webhook tool
You give Vio a URL and a signing secret. When the agent decides to call the tool, Vio POSTs the tool arguments to your endpoint, waits for your response, and speaks the result back to the caller. Use it to:
- Look up an order or account status
- Create a support ticket
- Check availability for a slot
- Book a demo or appointment
This is the bridge to your own systems, and it pairs well with no-code automation platforms like Zapier, Make, or n8n — point the webhook at a flow and the agent can trigger it live on a call.
Built-in / preset tools
One-click, first-party tools you can turn on without any code:
- Schedule a callback (
schedule_callback) — lets the agent book its own future call with the caller. This powers Callbacks. - Echo — a diagnostic tool that simply returns what it was given, handy for testing that tool-calling works.
Integration tools
Actions exposed by connected Integrations. When you connect a service, its actions become tools the agent can call. Some connectors are in beta or coming soon.
| Kind | You provide | Best for |
|---|---|---|
| Custom webhook | A URL + signing secret | Anything in your own stack; Zapier / Make / n8n flows |
| Built-in / preset | Nothing — one click | Callbacks (schedule_callback), diagnostics (Echo) |
| Integration | A connected account | Actions from services you’ve linked |
How to add a tool to an agent
Build the tool
In the Tools view, create the tool — for a webhook tool, enter its URL and signing secret. This defines the tool once for your whole workspace.
Enable it on the agent
Open the agent, go to its Tools tab, and enable the tools that agent should have. Each agent only gets the tools you switch on, so a support agent and a sales agent can carry different toolsets.
Test it
Place a test call and prompt the scenario that should trigger the tool. Confirm the agent calls it and speaks back the result. See Test your agent.
Reference a tool in your system prompt if you want to nudge when the agent uses it — e.g. “When the caller gives an order number, use the order-lookup tool before answering.”
Frequently asked
Q. How do I secure my webhook tool? Each custom webhook tool has a signing secret. Verify the signature on the incoming request at your endpoint so you know the POST genuinely came from Vio and not a spoofed caller.
Q. Does a failing tool drop the call? No. If a tool errors or times out, the agent degrades gracefully — it tells the caller it couldn’t complete that step and continues the conversation. A broken webhook never hangs up the line.
Q. Why enable tools per agent instead of globally? So each agent carries only what its job needs. Building in the Tools view and enabling per agent keeps a support agent from accidentally exposing a sales-only action, and vice versa.
Q. Can the agent book its own follow-up call? Yes — enable the Schedule a callback preset tool. The agent can then book a future call with the caller, which runs through Callbacks.
Next
Score and route what happens after the call in Analysis, actions & fulfilment, or tune call behaviour in Advanced settings.