Reference
Concepts
Seven ideas the rest of the product assumes you already have.
What is sent to Amazon today. Of the changes described here, MerchPPC sends the kinds it has confirmed against Amazon: a target's bid, a campaign's budget, a negative keyword and a new Auto campaign. Not sent yet: an ad group's default bid; a campaign's placement adjustments; a campaign's bid strategy; a campaign's audience bid adjustments; pausing or enabling a target, an ad, an ad group or a campaign; a negative product; removing a negative keyword; removing a negative product; promoting a search term to a keyword; adding a product target; adding a product to an ad group; adding products to a new ad group; a new manual campaign; a new Sponsored Brands campaign; one Auto campaign per product from a selection; splitting a campaign; a Sponsored Brands keyword's bid; a Sponsored Brands target's bid; a Sponsored Brands theme's bid; pausing or enabling a Sponsored Brands campaign, ad group or ad; a Sponsored Brands negative keyword; a Sponsored Brands negative product; a price change; adding a missing product; republishing a product; deleting a product. The extension shows those as “Not available yet” and holds them back until each one is confirmed.
Seven ideas the rest of the documentation leans on. Each is short, and each one explains a decision you will otherwise find strange.
Break-even ACoS
ACoS is what you spent divided by what you sold. It tells you nothing on its own, because it does not know what you keep.
Break-even ACoS is the number that does. It is the share of a sale that is yours — the royalty divided by the sale price. Spend below it and the sale made money; spend above it and it did not.
On Merch, this differs enormously between products. A $19.99 shirt and a $34.99 hoodie do not have the same break-even, and neither does the same shirt in a different marketplace. Amazon's console has no way to know your royalty, so it cannot show you this column. The extension can, because it read your sales.
This is the single most useful number in the product, and it is why so much of the interface is built around it.
Local-first
Your data lives in your browser, in a database the extension keeps on your machine. It is not uploaded, and there is no copy of it on a server.
The trade is real and worth stating in both directions: nobody else holds your numbers, and there is no cloud backup either. Clear the extension's storage and the history re-syncs from Amazon — slowly, because the first sync is the long one.
Complete days
A day is only counted once it has ended in Los Angeles — the timezone Amazon's reporting uses for every marketplace — and been fetched afterwards. Today's numbers move; yesterday's usually do not.
Every comparison in the product follows from this: it compares equal counts of complete days, and "today" never gets a comparison at all, because there is no hour-of-sale data to compare against.
The queue
Nothing reaches Amazon without passing through the Publish queue, and the queue waits for you. Bids, budgets, negatives, new campaigns, prices — all of them stage first.
This is the mechanism, not a setting. There is no mode in which the product acts on its own.
Grain
The level a thing is being talked about. A campaign, an ad group, a target, an ad, a search term, a negative, a product, a variant — and gap, which is the absence of one.
Most confusion in advertising tools is grain confusion: a number that is true at the campaign level being read as though it were true of a keyword. The extension names the grain everywhere it can.
Proposals
Software can compute. It cannot know that a product with terrible numbers is one you are about to relaunch, or that a keyword you are losing money on is one you are deliberately buying to hold.
So the product proposes and you decide. A lookout that proposes ten things and has three approved has done its job — the other seven were the conversation working.
Where numbers come from
Some numbers in the product are yours and some are public. Sales, royalties and ad spend come from your own Merch and advertising accounts and stay in your browser. Best Sellers Rank, review counts and search rank are public facts about a listing, read by your browser from Amazon and kept alongside your own data; see Rank tracking. A phrase you check for trademarks is the one thing sent to the site, and it is not kept; see Trademark checks. What the product tells you happened, and when, is in the Activity tab; see Notifications and messages.