Amazon is the tightest SKU limit you will meet
Clover takes 100. Amazon takes 20, and 20 is the number your catalogue has to fit.
Items pair up by SKU, so the shorter limit governs, and Amazon’s 20 characters is the tightest of any channel we support. Clover’s 100 is not what will catch you out. Twenty goes quickly if you build codes out of words: a product name, a colour and a size strung together is usually over the line before you have finished typing it, and it gets truncated on the way to Amazon.
The failure is quiet, which is what makes it worth an hour before you connect rather than a reconciliation afterwards. We truncate at the channel’s limit instead of refusing to send, so nothing errors and nothing turns red. The shortened code just stops matching the item it came from, the count stops moving on that line, and you find out when two numbers disagree. Shorten the pattern once and it never starts.
Timing is the easy part of this pair. Neither Amazon nor Clover has to be checked on a timer; each reports what has changed at the point it changes, so a sale at the register reaches the marketplace with no scheduled look in between. Several channels do have to be polled, and this pair avoiding that is why a till and a marketplace can share one shelf without much drama.