Get a product

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

Annotations already cover read-only and open-world behavior, and the description goes well beyond them: it discloses the billing model (units of $0.001 at list price), that failed calls are not billed, and that cost varies by platform with a per-call unit range (aliexpress 1–2, amazon 2–32, others 1). That is exactly the operational context an agent needs before spending money on a call.

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?

Purpose is front-loaded in one line, followed by a compact per-platform list and a closing cost note. Every element carries load — no restated title, no filler — and the hierarchical form is easy to scan before a call.

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?

With no output schema, the description compensates by naming the returned fields (variants, images, specifications, seller, delivery, price). Combined with full per-platform parameter guidance and the cost model, there is nothing material an agent needs in order to invoke this correctly that is missing.

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%, but the schema's `params` property is a bare `additionalProperties: {}` bag; the description is what actually tells the agent which keys are valid on which platform (currency/include/language/region per platform) and which are mandatory. It also clarifies the id-vs-top-level relationship that the schema leaves implicit.

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?

Opens with a precise scope statement — 'One product in full' — and enumerates exactly what the record contains (variants, images, specifications, seller, delivery, price). That framing alone separates it from the sibling search_products/search_products_by_image tools, which return collections rather than a single hydrated record.

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 concrete call context: the accepted platform set, which parameters each platform takes, which are required (marked with *), and that id may be supplied at the top level. What it doesn't do is state exclusions or route the agent — e.g. it never says 'search first to obtain an id' or that an invalid id on one platform can't be resolved via another.

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