Set Up

The fastest way to add Poku to your voice AI agent is to configure it as a custom function or tool call on your platform of choice. This walkthrough uses email capture as the example — one of the most common use cases, since emails are hard to capture reliably over voice. If you’re using Retell AI or Vapi, see the platform-specific guides: Retell AI · Vapi

Create a new custom function or tool

In your voice AI platform, navigate to the tools or functions section and create a new custom function.

Configure the HTTP call

Set the tool name, description, method, URL, and authorization header:

Field	Value
Name	`send_sms`
Description	`Use this tool to text the customer`
Method	`POST`
URL	`https://api.pokulabs.com/messages/sms`
Authorization	`Bearer <your-poku-api-key>`

Define the input parameters

Expose the following parameters so your agent can populate them at call time:

Parameter	Type	Required	Description
`message`	string	Yes	Could you reply with your email address here?
`to`	string	Yes	The recipient’s phone number in E.164 format. This is typically a dynamic variable depending on the platform — e.g. `{user_number}` or `{customer_phone_number}`. For testing, hardcode your own number.
`waitTime`	number	No	Seconds to hold open waiting for a reply. Set to `60` for email capture.

Update your agent prompt

Tell your agent when and how to use the tool. See the example prompt below.

Example agent prompt

# Role
You are a front desk agent for ACME.

# Task
Collect the customer's email address using the following process:

## Step 1: Offer the text option
Ask the customer: "I'll need to collect your email address. Would you prefer to text it to me instead of saying it out loud?"

## Step 2: Handle their response
- If the customer agrees to text: proceed to Step 3.
- If the customer prefers to say it verbally: listen and collect the email address they speak aloud.

## Step 3: Send the text request
Say: "Perfect — I'm sending you a text right now where you can reply with your email address."
Then immediately call the send_sms tool.

## Important
Always wait for the customer's preference before calling the tool.

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Messages

Send a message and wait for a reply.

Forms

Send a structured form and receive all fields back.

Channel Cards

Expose specific channels to your agent at runtime.

Follow Up Time

Capture replies that arrive after the call ends.

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Example agent prompt

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Messages

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Messages

Forms

Channel Cards

Follow Up Time

Example agent prompt

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