upc_search

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

Annotations already declare readOnly, idempotent, non-destructive and openWorld, so the safety profile is covered and the bar is lower. The description confirms the external UPC database (consistent with openWorldHint) but says nothing about result counts, pagination, fuzzy vs exact matching, or empty-result behavior — meaningful for a search 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 front-loaded sentence with no filler. Nothing in it is redundant or 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?

For a one-parameter read-only search this is close to adequate, and the annotations carry the safety semantics. But with no output schema, the description is the only place an agent could learn what a result looks like (product name, brand, UPC, image) or how it relates to upc_lookup — and it supplies neither.

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 there is a single required param, so the schema does the documentation work. The description does add one useful nuance beyond the schema — that the query is a product name rather than a UPC code — but nothing on format, partial matching, or length constraints.

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 ("Search products by name in the UPC item database"), which is clear on its own. It stops short of differentiating from the sibling upc_lookup, so an agent cannot tell from the description alone whether to search by name or look up by code.

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?

No when-to-use guidance, no exclusion of the alternative path. The presence of upc_lookup in the sibling list makes the missing routing decision material — a user supplying a 12-digit code versus a product name is exactly the case the description should disambiguate.

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