Quick start

Six steps. The first three take minutes; the two after them are where the value is; the last one waits on data.

1. Create the account

Sign up, confirm your email, and turn on two-step verification before you connect anything.

2. Connect Amazon — both connections

Amazon Ads first, then SP-API for the same seller. Ads gives Vendlen the Seller ID that SP-API attaches to, which is why the order is not interchangeable.

See Connect your Amazon account.

3. Write a Product Line

This is the step people skip, and the one that decides how good everything downstream is.

A Product Line carries the context the Agent reasons inside and the economics every decision resolves against — break-even ACOS, target ACOS, max bid. Without it there is nothing for a recommendation to be measured against.

You do not have to start from a blank form: the Agent can interview you and draft it.

Set one as the account default so unassigned products still have numbers.

4. Group your variants

Tie the variants of one product — colours, sizes, materials, styles, quantities — into a Product Group. This decides what counts as evidence for what — a term that is thin on one ASIN is often dense across its group. See Decision scope.

5. Enter your cost of goods

Without COGS, every profit figure is missing its largest deduction and looks better than it is.

6. Wait for evidence, then read a Decision Brief

Nothing useful appears on day one. The Analyst compares consecutive periods, and a new connection has none to compare yet. See Your first week.

When briefs do appear, read the reason and the evidence, not just the action. A brief you disagree with is telling you something about your account that the numbers alone did not.

Then, when you are ready

Configure one Automation rule and check Preview Changes before its first run, so you see what it will do rather than reading about it afterwards. One rule at a time is worth more than any single rule setting.

The shortest version

Do this	Because
Connect both APIs	One alone leaves half the picture
Write the Product Line properly	Everything downstream reads it
Group variants	Decides what counts as evidence
Enter COGS	Otherwise profit is fiction
Stage rules before trusting them	You find out what they do without paying for it