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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, closed-world), so the bar is lower. The description adds real behavioral context beyond them: unmatched names are 'counted and left out — never guess,' and it discloses what each entry contains and where prices appear only when active ingredients match.

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-loaded with the core purpose and the routing rule, then the return shape, then next steps. Backticked field names aid scanning. The 'Next:' workflow block is slightly verbose but each line adds routing value, so it largely earns its place.

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?

There is no output schema, but the description compensates by enumerating the per-entry fields (usClass, guidance, US product, price start condition, card) and the unmatched-name behavior. Only 'locale' and 'channel' remain unexplained for a four-parameter tool.

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 0%, so the description must carry the load. It documents 'brands' (two to six names as typed) and 'country' (disambiguates brands of the same name sold in different places), but says nothing about 'locale' or 'channel', leaving half of the four parameters undocumented in both places.

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 ('What several medicines from another country are in the US') and immediately distinguishes the batch scope from the singular sibling: 'One medicine: use find_us_equivalent.' An agent can tell it apart from find_us_equivalent without opening either 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?

Explicit when-to-use ('person names two or more medicines that are not US products... asks what they are here') and an explicit alternative plus its selecting condition ('One medicine: use find_us_equivalent'). It also specifies the follow-up path (offer compare_basket), leaving nothing to inference.

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