Add multiple variants to a Shopify product with option values, prices, SKUs, and stock tracking, removing the default placeholder when adding the first real variant.
Add variants to a product. The SKU goes inside inventory_item, not on the variant. When the product still carries its default placeholder variant, pass the strategy that removes it.
| Name | Required | Description | Default |
|---|---|---|---|
| variables | Yes | The variants to add. |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=false and openWorldHint=true, so the safety profile is covered. Beyond that, the description discloses a genuine, non-obvious behavioral quirk (the default placeholder variant and the strategy that removes it) that the schema alone does not surface. It stops short of covering return or partial-failure behavior for a bulk mutation.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
Three short sentences with the core purpose front-loaded and zero filler. The SKU-placement note is a slight non-sequitur in ordering but each sentence carries useful information.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a bulk mutation with no output schema and full schema coverage, the description covers purpose, a key gotcha, and conditional strategy guidance. It omits what happens on partial failure across a bulk array, a minor gap given the otherwise complete coverage.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema coverage is 100%, so the schema already documents every field. The description still adds structural meaning beyond the schema by clarifying that the SKU belongs in `inventory_item` rather than on the variant, and by explaining when the `strategy` value is needed.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description opens with a specific verb and resource: "Add variants to a product," which is clearly distinct from siblings such as shopify_product_create, shopify_product_update, and shopify_variant_inventory_level. It does not explicitly name or contrast with those siblings, so it stops short of full differentiation.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
It gives targeted conditional guidance for one scenario ("When the product still carries its default placeholder variant..."), which is useful context, but it never states when to choose this bulk-create over alternatives or what prerequisites apply. Usage is implied rather than spelled out.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.