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

Annotations already declare readOnly, idempotent and non-destructive, so the safety profile is covered. The description adds genuinely new context beyond them: 'Open tool — no API key required,' which tells the agent no auth setup is needed. It stops short of describing error behavior for a missing handle or any pagination/size limits.

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?

Two tight sentences, zero filler. The core purpose and its field list come first, with the auth note following as a short parenthetical-style clause.

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 enumerating the return payload, and the single required parameter is fully covered by the schema. For a simple read-by-handle tool, an agent has everything needed to invoke it correctly.

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?

Only one parameter and schema description coverage is 100%, so the schema already documents the handle and gives an example. The description adds no format or normalization detail beyond it, making the baseline 3 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?

States a specific verb (Get), resource (full details for one product), scope (by its handle), and enumerates the returned content (variants, SKUs, options, prices, images, spec metafields). It clearly reads as the detail-fetch counterpart to search_products, though it never names that sibling explicitly.

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 rather than stated: 'by its handle' signals this is a follow-up lookup after obtaining a handle elsewhere, and the schema references search_products as the source. There is no explicit when-to-use/when-not guidance or contrast with get_price_and_lead_time or request_quote.

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