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

Annotations already declare readOnlyHint and openWorldHint, so safety is covered. The description adds genuine behavioral context beyond that: recommendation lists vary by product, and alternatives/upsell categories dominate over style-with/series, which primes the agent for inconsistent return content.

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 crisp clauses, front-loaded with the core action, and every element (scope, variability, sibling routing) carries information. No padding.

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 an output schema present, return contents need no explanation, and annotations cover the safety profile. The description supplies the scope, the variability caveat, and the routing alternatives, which is everything an agent needs for this single-parameter recommendation call.

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 product_id description already specifies a numeric H&M product id sourced from a listing/search result. The description's 'one product ID' adds no format or semantics beyond the schema, so the baseline 3 applies.

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 (H&M recommendations for one product ID), and explicitly distinguishes itself from hm_product (details) and hm_search (finding products). An agent can identify the tool's role without opening any schema.

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?

Names the two relevant alternatives (hm_product, hm_search) and their roles, giving clear context for when this recommendation tool is the right pick. It lacks explicit when/when-not phrasing, but the routing intent is unambiguous.

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