Merit · PIM · Concept explainer

What a variant axis is

This is the idea behind MSP-392, the variant creation flow, and DEC-0172, the decision that made Region a variant axis on Smartphones. Six diagrams, each with a short caption underneath.

For Brian Arfi Faridhi, Product
Sources PRD PIM Category and Attribute Structure sections 5.2 and 5.4, MSP-392 Variant Creation Requirement sections 2.1 to 2.3, Master PIM Documentation section 2.1

01An attribute, or an axis

A category has many attributes. Only some of them are promoted to axes.

Smartphones category

All attributes of the category Storage Colour Region Weight Screen size Battery capacity Promoted to variant axes stays a plain attribute stays a plain attribute stays a plain attribute Storage + Colour + Region create separate buyable items

An axis is an attribute that Merit has marked as the thing that makes two items different buyable versions of the same product. Colour is an axis on T-shirts. Storage is an axis on phones. Weight is not an axis, because nobody buys a different weight of the same phone. It stays on the product page as information only.

This is the one idea to keep

Every attribute describes the product. Only an axis splits the product into separate Variants a buyer can choose between. Getting this wrong is what created the iPad problem in section 5.

02Axis values multiply into a grid

Two axes on Smartphones: Storage and Colour. Every combination becomes its own child SKU.

Storage [128GB, 256GB] × Colour [Black, Blue, Titanium]

Six boxes, six child SKUs. FR-17 says every combination of axis values generates a child SKU with its own barcode field, its own stock and its own price. Nobody enters these six by hand. The system builds the grid from the axis values.

Add a third axis: Region [UAE, International, US]

6 Storage x Colour x 3 Region values 18 Storage x Colour x Region child SKUs

Adding one axis with three values did not add three SKUs. It multiplied the whole grid by three. That multiplication is the cost of adding an axis, and it is why an axis is never a free addition to a category.

03The cap: five axes per category

FR-10 allows at most five variant axes per category. Smartphones spends three of them today.

Smartphones variant axes, five slots

Storage Colour Region UAE / Intl / US free free 3 of 5 used

DEC-0172, decided 19 August, made Region the third axis on Smartphones, with allowed values fixed to exactly UAE, International and US. Two slots remain, and nothing else is queued for this category.

04Who may create an axis

A catalogue admin can. A seller can never.

Two lanes

Catalogue admin Create a new axis Set the allowed values list FR-19 What the seller can do Pick a value from the list Blocked: add my own axis FR-18, OFF for Smartphones Why FR-19 pins values to an admin list, so an axis cannot become free text. DEC-0172 turned FR-18 OFF for Smartphones and Electronics, so a seller cannot invent a fourth axis or a fourth value.

A seller-invented axis fragments the category permanently, and FR-17 means every existing product in that category gains a cross product of empty SKUs. The rule stays in the schema, not only in a document, so nobody rebuilds a hole for it later.

05The failure this prevents: the iPad case

One Variant with two different physical items hidden behind it. This is the case that made DEC-0172 necessary.

Before: Connectivity is not an axis

Variant iPad Pro 11 inch, 256GB, Space Black Offer A, Seller 1 WiFi unit, lower price Offer B, Seller 2 WiFi + Cellular, higher price App shows the lowest-price Offer Buyer selects the Variant, not the Offer, is charged the WiFi price, and receives the WiFi-only unit instead of Cellular. Nothing errors. Found only in returns.

After: Connectivity is a variant axis

Connectivity axis added: WiFi, WiFi + Cellular Variant: iPad Pro 11 in, 256GB, Black, WiFi one Offer, its own price and stock Variant: iPad Pro 11 in, 256GB, Black, WiFi + Cellular one Offer, its own price and stock Buyer picks the version they want, and receives it

This is the fix DEC-0172 applied to Region, and the same fix MSP-392 applies to Connectivity. One Offer never carries two different physical items. When two real items collide on the same axis values, the fix is a new axis, not a second Offer.

06When the right axis does not exist yet

The seller cannot force a new axis into existence. The flow fails loudly and routes the decision to an admin.

Create is blocked with a named error Axis request raised against the category Catalogue admin decides Nothing written while it waits

No duplicate Variant and no Offer go live during the wait. A silent merge or a duplicate only surfaces after a customer has already received the wrong item, which is the exact failure section 5 shows.

Merit Incentives · PIM · What a variant axis is
Sources: PRD PIM Category and Attribute Structure, MSP-392 Variant Creation Requirement, Master PIM Documentation.