Tools

Tool

Something a playbook can call mid-conversation: functions, API tools, MCP tools, integrations, and the built-in system tools. Each also has a step form for use at a fixed point in a workflow.

Also asked as:

things the assistant can do besides talking
let the agent take an action in another system
what can the agent actually do besides chat
actions the assistant can take in other systems

Related: Agent tools · System tools

Documented in: Agent tools

Function

Custom JavaScript that runs in Voiceflow’s sandbox and returns through a named path. Code runs remotely in an isolated sandbox; it communicates back only through its return value (outputVars, next, trace) and can make HTTP requests with fetch.

Also asked as:

write custom code the agent can run
a JavaScript tool that calls an external API
return different outcomes from my own code

Related: Function step · Function path · Function variable · Code step

Documented in: Function tool › Creating a Function tool · Function tool › How function code works · Function tool › Making API requests with fetch

Function tool

A function exposed to a playbook as something it can call. The agent calls it on its own when the conversation requires it; in a workflow the same function runs through a Function step.

Also asked as:

let the assistant run my custom code when it needs to
expose a function to a skill
give a playbook access to my JavaScript
custom logic the agent can invoke

Related: Function · Function step

Documented in: Function tool › Using the Function tool · Function tool › In a playbook

Function path

One of the named exits a function can return through. Paths are what let a function branch rather than just return a value. They apply in Function steps only, not inside a playbook.

Also asked as:

make my function send the flow one way or another
success and failure exits from custom code
multiple outcomes from one function
route the workflow based on my code’s result

Related: Function · Function step

Documented in: Function tool › next: choosing a path

Function variable

An input or output a function declares. Inputs are passed in when it runs (args.inputVars); outputs are written back for later steps to read (outputVars).

Also asked as:

pass a value into my code and get one back
read the function’s result in a later step
declare inputs and outputs for my function
what a function receives and returns

Related: Function · Variable

Documented in: Function tool › Accessing input variables · Function tool › outputVars: setting variables

API tool

A saved HTTP request an agent can make, tested from the editor and used in a playbook (the agent decides when) or a workflow (the API step, at a fixed point).

Also asked as:

call a REST endpoint from the assistant
make an HTTP request to our own backend
connect the bot to an API that has no prebuilt connector

Related: API step · API tool variable · Asynchronous tool call · Secret

Documented in: API tool › Creating an API tool · API tool › Testing the API tool · API tool › Using the API tool

API tool variable

An input an API tool substitutes into its request, so one saved request can serve many calls.

Also asked as:

put a variable into the request URL or body
parameterise a saved request
a placeholder in the request that changes per call
dynamic values in an API request

Related: API tool

Documented in: API tool › Creating an API tool

Asynchronous tool call

Running an API or Function tool in the background so the conversation continues immediately: fire and forget when the response is not needed, deferred response when it still matters. The async toggle is set per instance, not per tool.

Also asked as:

don’t make the visitor wait for a slow request
run a call in the background and carry on talking
log something without holding up the reply

Related: API tool · Function

Documented in: API tool › Running API tools asynchronously · Function tool › Running Function tools asynchronously

Integration

Calls a third-party service such as Salesforce, Shopify or Zendesk through a prebuilt connector: Airtable, Gmail, Google Sheets, HubSpot, Make, Salesforce, Shopify, Twilio and Zendesk each expose a set of actions.

Also asked as:

connect our CRM or helpdesk to the assistant
a prebuilt connector to a third-party app
send an email or create a ticket from the bot

Related: Integration step · Tool

Documented in: Agent tools › Available integrations · Agent tools › Setting up an integration · Airtable tool · Gmail tool · Google Sheets tool · HubSpot tool · Make tool · Salesforce tool · Twilio tool · Zendesk tool

System tools

Native capabilities built into Voiceflow that need no setup: knowledge base search, web search, buttons, cards, carousels, skip turn, end and call forward. Enabled by a toggle at the agent level (then available in every playbook) or per playbook, where a local override can change a tool’s settings and trigger.

Also asked as:

the built-in tools the assistant comes with
switch on web search or buttons for the agent
change a built-in tool’s behaviour in one playbook only

Related: Knowledge base tool · Buttons tool · Web search · Skip turn · End tool

Documented in: System tools › Enabling system tools · System tools › Local overrides

Knowledge base tool

The system tool that searches the knowledge base to answer a question. Configurable: the trigger, a custom query, query re-writing, the chunk limit (1–10, default 3), metadata filtering, tool messages, and source URLs in the reply.

Also asked as: