Skip to main content

Documentation Index

Fetch the complete documentation index at: https://docs.pokulabs.com/llms.txt

Use this file to discover all available pages before exploring further.

Add Poku as a custom tool in any Vapi agent — giving your voice AI the ability to text customers, capture structured data, loop in a manager, and more.

​
Use cases

Email capture over SMS

Agent sends a text mid-call. Customer replies with their email. Agent reads it back and continues.

Form capture via WhatsApp

Agent sends a form link over WhatsApp. Customer fills it out on their phone while still on the call.

Loop in a manager

Agent texts a manager to check transfer availability before handing off — no dead air for the customer.

Quote approval via Slack

Agent pings a Slack channel for sign-off on a custom price, then relays the answer to the customer.

​
Setup on Vapi

1

Create a new tool

In your Vapi dashboard, go to Tools and click Create Tool. Select Function as the tool type.
Creating a new tool in Vapi
2

Name and describe the tool

Give the tool a name and description your agent will use to decide when to call it. For example: send_sms, “Send an SMS to the customer and wait for their reply.”
Naming and describing the tool in Vapi
3

Define the parameters

Add the parameters your agent will pass — for example to, message, and waitTime. These map directly to the Poku API fields.To send the message to the customer’s phone number, pass {{customer.number}} in the to field. See Vapi dynamic variables for details.
Defining parameters in Vapi
4

Set the Server URL

Enter the Poku API endpoint for the action you want:
ActionURL
Send SMShttps://api.pokulabs.com/messages/sms
Send WhatsApphttps://api.pokulabs.com/messages/whatsapp
Send Slack messagehttps://api.pokulabs.com/messages/slack
5

Set the timeout

Set the tool timeout to be longer than the waitTime you plan to pass to Poku. If your waitTime is 30 seconds, set the timeout to at least 40 seconds.
6

Add the authorization header

Under HTTP Headers, add:
KeyValue
AuthorizationBearer <your-poku-api-key>
Adding the authorization header in Vapi
7

Save and add to your agent

Hit Save. Then navigate to your agent and add the tool from the tools list.
8

Update your agent prompt

Update your agent’s system prompt to reference the tool by name so it knows when and how to call it.

​
Advanced: Async context injection for call transfers

Standard tool calls stall the conversation while waiting for a response. The Vapi agent will say “hold a second. Just a second.” However, with async context injection, Poku pushes the reply directly into your live Vapi session — so your agent can keep the conversation flowing while waiting for a human to respond in the background.

​
How it works

  1. Your agent calls a Poku tool that notifies a human
  2. Poku immediately returns success so the agent can continue the conversation
  3. When the human replies, Poku injects their response into the live Vapi call using your Vapi API key
  4. The agent receives the context and acts on it mid-conversation — no stalling

​
Setup

Step 1 — Add your Vapi API key to Poku Go to dashboard.pokulabs.com/integrations under Integrations > Vapi and paste in your Vapi API key. This allows Poku to inject context into your live Vapi sessions asynchronously. Step 2 — Create the custom tool in Vapi Create a new Function tool with the following:
FieldValue
Namecheck_if_rep_available_for_transfer
Parameter 1message (required, string)
Parameter 2async (required, boolean) — must be true
Server URLhttps://api.pokulabs.com/hitl/notify-human/<channel_id>
Authorization headerBearer <your-poku-api-key>
Configuring the notify-human tool in Vapi
Use the notify-human endpoint. Your <channel_id> comes from your Poku channel card — copy it directly from the card in your dashboard.
Step 3 — Write the agent prompt Give your agent explicit instructions on when to call the tool and how to handle the injected response. Example: 
If customer asks to speak to a human
First: Call check_if_rep_available_for_transfer
Then: Respond with "I am checking if my manager is available, but I can keep helping you in the meantime."

When a manager becomes available:
   (Triggered by message from human manager)
   Interrupt politely: "Quick update — someone from our team just became available. Would you like me to transfer you now?"
   If yes: Call transfer_call tool to initiate transfer
   If no: Continue assisting the customer