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

Annotations cover the safety profile (readOnlyHint, openWorldHint), and the description adds real behavioral context: availability is 'live,' reviews are 'real customer' data with fit tags, and reviews appear only 'when the product has any' — a conditional disclosure not derivable from the schema or annotations.

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?

Front-loads the resource and its payload in one dense sentence, then adds the id-provenance note. Every clause earns its place, though the first sentence is long enough to be slightly heavy for a single read.

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?

For a one-parameter detail tool with a full output schema, the description supplies enough: what it returns, when reviews exist, and where the id comes from. It does not restate return structure, which the output schema already handles, so nothing essential 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 description coverage is 100%, and the description's note that product_id is 'the numeric id from a listing/search result's id field' restates the schema's own wording rather than adding new syntax or format constraints. Baseline 3 when the schema already does the work.

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 resource and scope ('One H&M product's full detail') and enumerates exactly what it returns: per-color, per-size pricing, live availability, aggregate rating, and reviews with fit-feedback tags. It explicitly distinguishes itself from hm_listing and hm_search, so an agent can route without inspecting schemas.

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 names the sibling tools whose output lacks this detail ('not available from hm_listing or hm_search') and tells the agent to source product_id 'from a listing/search result's id field,' implying the correct call sequence. No explicit when-not or exclusion beyond that, so slightly short of a 5.

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