Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already establish that this is a read-only, idempotent, non-destructive operation. The description adds useful behavioral detail beyond annotations: the simulation uses VAT-exclusive price, category commission rules, fixed fee, real Cargus AWB courier estimates by weight band, and factory cost from labor plus reference-month average material.

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?

The definition is a single dense but front-loaded sentence that begins with “[Analysis] Margin of one SKU” and then enumerates the calculation components. It is efficient, though the long clause chain is slightly harder to scan than a structured list.

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?

An output schema exists, so return values need not be described in detail. Given the read-only annotations and partial schema coverage, the description provides enough context about what is simulated and how the margin is composed, though it could say more about when to choose this tool.

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 67%, and the description adds meaning for several parameters: prices[] for comparing multiple shelf prices, account scoping, gross price, and category override. It does not explain vat_percent, and sku is left to the schema, so the baseline of 3 is appropriate.

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 names a specific operation and resource: margin simulation for one SKU on one account, with a clear breakdown of price, commission, fees, courier cost, factory cost, and margin. It is distinct from sibling tools, though it does not explicitly contrast itself with alternatives.

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?

Usage is implied by the analysis/margin-simulation framing and the note that several prices can be compared via prices[]. However, it does not state when to use this instead of related siblings such as offers_get, commissions_get, or price_parity_check, nor does it give exclusions or prerequisites.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.