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

Annotations already cover readOnly, idempotent and non-destructive, so the description adds real value by disclosing what is returned ('stock and pricing summary'), what is omitted ('photo galleries and custom fields'), and the required scope ('items:read'). It does not describe not-found behavior, but the disclosure beyond annotations is substantive.

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?

Three tight sentences: purpose first, then return scope and limits, then the auth requirement. Every sentence adds information with no repetition of the title or schema.

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, describing the return contents and omissions is necessary and done here, and the auth scope is stated. For a single-parameter read tool this is nearly complete, missing only error/not-found semantics.

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?

With one parameter at 0% schema description coverage, the description carries the burden and does clarify that item_id is a UUID, consistent with the schema's UUID pattern. It adds no other detail about the identifier's origin, so it only partially compensates for the coverage gap.

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 and resource ('Read one inventory item by UUID') and adds scope ('including archived or sold items visible to the API user'). This clearly distinguishes it from salesbinder_list_items, which returns many items without a UUID.

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?

The 'one item by UUID' framing clearly signals when this tool applies versus the list_* siblings, and the note about archived/sold visibility clarifies useful edge-case coverage. It stops short of explicitly naming salesbinder_list_items as the alternative when only a name/filter is known.

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