How to Send a Zapier Webhook to OpenAI and Get a Summary Back

Catch any incoming payload in Zapier, pass it to the OpenAI Chat Completions API, and reuse the summary in later steps.

8 minBeginner

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A Catch Hook trigger in Zapier gives you a public URL that accepts any POST request. Once data lands there you can hand it to OpenAI and turn long text into a tidy summary that the rest of your Zap can use. This guide wires that up end to end without writing a server.

What you need

A Zapier account (the free plan includes Webhooks by Zapier)
An OpenAI account with an API key from platform.openai.com
A source that can POST JSON to a URL (a form, app, or curl)

Step 1: Create a Catch Hook trigger

Make a new Zap and pick Webhooks by Zapier as the trigger app. Choose the Catch Hook event. Zapier shows you a unique URL such as https://hooks.zapier.com/hooks/catch/123456/abcde. Copy it.

Zapier - Choose trigger event

Trigger: Webhooks by Zapier

Event: ( ) Retrieve Poll

(•) Catch Hook

( ) Catch Raw Hook

Custom Webhook URL:

https://hooks.zapier.com/hooks/catch/123456/abcde

The Catch Hook event exposes a public URL on the next screen.

Step 2: Send a test payload

Zapier needs a sample to learn the field names. Fire a quick POST from your terminal so the trigger records a real example.

zsh - test the catch hook

$curl -X POST https://hooks.zapier.com/hooks/catch/123456/abcde \

$ -H "Content-Type: application/json" \

$ -d '{"title":"Q3 notes","body":"Long meeting transcript text goes here..."}'

{"status":"success","attempt":"01H..."}

Step 3: Add an OpenAI action

Add an action step. You can use the built-in OpenAI app, but the most flexible option is Webhooks by Zapier with the POST event so you control the exact body. Point it at https://api.openai.com/v1/chat/completions and set the Authorization header.

Zapier POST body (JSON)

{
  "model": "gpt-5-mini",
  "messages": [
    { "role": "system", "content": "Summarize the text in 3 bullet points." },
    { "role": "user", "content": "{{body}}" }
  ],
  "temperature": 0.3
}

Header format

In the Headers section add Authorization with the value Bearer sk-your-key, and Content-Type with application/json. The word Bearer plus a space must come before the key.

Step 4: Map the reply into later steps

OpenAI returns the text under choices.0.message.content. Open the action output in Zapier and pick that field for any downstream step, such as appending a row to a sheet or sending a Slack message.

Result: a meeting transcript POSTed to your hook comes back as three clean bullet points within a couple of seconds, ready to drop into Slack or Notion.