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

Annotations already mark readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds valuable context: the distinction between containerised gateway trade and nationwide duty receipts, noting the response itself flags this, and explicitly states 'No API key required.' No contradictions with 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?

Four sentences, each carrying distinct information: function, usage direction, data-caveat, and attribution. It is dense but not bloated. Slightly longer than the ideal two-sentence example, but no redundant filler.

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?

No output schema, but the description enumerates all key response components (gateways, trend, commodity chapters, tariff burden, studies) and provides usage context, exclusions, and a data interpretation caveat. For a read-only profile tool with minimal parameters, this is sufficiently complete.

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 50% (origin and top_n have descriptions; detail and months do not). The description indirectly refers to top_n via 'top commodity chapters' and months via 'trend', but does not clarify the 'detail' enum values or default behavior. Some added semantics, but incomplete for two parameters.

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 returns a comprehensive country-level profile: US containerised import volume and value through major gateways, trend, top commodity chapters, effective tariff burden, and related studies. It explicitly differentiates from siblings by naming trade_query, tariff_burden, tariff_story, and compare as alternatives to avoid.

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 country-level question... instead of firing trade_query and tariff_burden separately.' Also gives clear exclusions: 'Do NOT use for a specific HS code (tariff_story) or a two-way comparison (compare).' This goes beyond implied usage.

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