The Scenario
A marketing manager got sign-off this morning on a one-time re-engagement campaign for 600 lapsed users. Each recipient gets a unique discount code. The user IDs are in column A of a Google Sheet, the discount codes are in column B. Customer.io's broadcast is set up and ready — broadcast ID 12345 — it just needs to be triggered with the audience list and each person's promo_code variable. The sales window closes in 48 hours.
The bad version:
- Read the Customer.io documentation for the broadcast trigger API, figure out how to pass a custom audience and per-recipient Liquid variables.
- Write a script that POSTs each user ID with their promo_code, handle pagination, test against a subset.
- Run it on the full list, discover that 40 user IDs returned "not found" errors because they were deleted, re-run excluding those rows.
The 48-hour window doesn't have room for a debugging session. The discount codes expire when the window does.
The Easy Way: One Prompt in SheetXAI
SheetXAI is an AI agent that lives inside your Google Sheet. It reads the audience list and variable data, and through its Customer.io integration can fire the broadcast trigger with per-recipient personalization for every row — in one operation.
Trigger Customer.io broadcast ID 12345 for all user IDs in column A of my sheet, passing the discount code from column B as a personalization variable called "promo_code"
What You Get
- The broadcast is triggered for each user ID in column A with their unique promo_code from column B passed as a Liquid variable.
- Column C gets written with "Triggered" for each successful row, or the error detail — "User Not Found," "Invalid ID," "Broadcast Inactive" — for rows that failed.
- User IDs that don't exist in Customer.io are flagged rather than silently dropped, so you know exactly who was missed.
- All 600 triggers fire in one operation with a result log you can use to confirm delivery.
What If the Data Is Not Quite Ready
Some user IDs in the sheet are email addresses, not numeric IDs — the broadcast requires IDs
Look up each email in column A against Customer.io to find the corresponding user ID, then trigger broadcast 12345 for each found user ID with the promo_code from column B as a Liquid variable. Write the resolved user ID to column C and the trigger status to column D.
I want to exclude users who have already made a purchase in the last 30 days — that flag is in column C
Trigger Customer.io broadcast 12345 only for rows where column C is not "Recent Purchase." Use user_id from column A and promo_code from column B as the personalization variable. Write trigger status to column D.
The audience spans two tabs — "Segment A" with one discount tier and "Segment B" with another
Trigger Customer.io broadcast 12345 for all user IDs in column A of the "Segment A" tab using promo_code from column B. Then trigger Customer.io broadcast 12346 for all user IDs in column A of the "Segment B" tab using the promo_code from column B. Write status to column C on each tab.
Validate that discount codes are non-blank, trigger only valid rows, log errors for the rest, and write a summary count in one shot
For each row in my sheet, check that the discount code in column B is not blank. If it's valid, trigger Customer.io broadcast 12345 for the user_id in column A passing the code as promo_code. If column B is blank, mark column C "Skipped — No Code." Write "Triggered" to column C for all successful rows and add a total count at the bottom of column D.
Doing the validation and the trigger in one prompt means the campaign fires clean — no empty promo codes going out to real people.
Try It
Get the 7-day free trial of SheetXAI and open your audience sheet with user IDs and discount codes, then ask it to fire the Customer.io broadcast before the sales window closes. You can also look at sending transactional emails from a sheet or the full Customer.io overview.