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

Annotations cover the read-only and open-world safety profile, so the description only needs to add context. It adds the fixed domain (row.gymshark.com) and the fact that results are normalized, which is meaningful beyond the annotations. It doesn't describe pagination or errors, but that is minor on a read-only single-lookup tool.

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?

One sentence states the action and resource, front-loading the key constraint (fixed domain), and the second sentence is a compact routing list. No wasted words.

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-value detail is not needed. For a single-param read-only lookup, the description plus annotations plus schema give an agent everything required to select and call the tool 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?

Schema coverage is 100% and the single parameter is fully documented in the schema. The description clarifies that the handle is a URL slug tied to the row.gymshark.com storefront, which adds a little context but is largely redundant with the schema description. Baseline 3 is correct.

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 (Fetch) and resource (normalized detail records for one Gymshark product), and identifies the lookup key (URL `handle`) as well as the fixed storefront domain (row.gymshark.com). This distinguishes it cleanly from the sibling list/browse tools.

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?

Explicitly routes the agent: use gymshark_products to browse, gymshark_collections for collections, gymshark_collection_products for collection items, and gymshark_product_recommendations for related items. This is a full when-to-use-this-vs-alternatives selection aid.

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