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

Annotations already declare readOnlyHint and destructiveHint, so safety is covered. The description adds valuable context such as 'No API key required' and warns that code-level origin rankings are 'not honest at chapter rollup granularity', offering behavioral nuance beyond the 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?

The description is well-structured, front-loaded with a clear value proposition, and every sentence contributes purpose, examples, alternatives, or access details. No redundant or fluffy content.

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 complex profile tool with 4 parameters and no output schema, the description thoroughly explains the data returned, usage scenarios, exclusions, and access. It does not detail the return format, but the absence of an output schema makes this less critical.

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 descriptions cover top_n and commodity, and the description adds essential context for commodity (HS2 chapter, not 6-10 digit). However, detail and months are not explained in the description nor fully in the schema, and with 50% schema coverage the description only partially compensates.

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?

The description clearly states the tool profiles an entire HS chapter in one call, listing specific metrics (imports, origins, duties, tariff rates, studies). It distinguishes itself from siblings by explicitly mentioning trade_query, tariff_burden, and tariff_story as alternatives.

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?

Provides explicit when-to-use guidance ('Use this to OPEN any commodity-level question') and examples. It names alternatives ('instead of assembling trade_query + tariff_burden per origin yourself') and exclusions ('for a specific 6-10 digit code call tariff_story instead').

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