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

Annotations already declare readOnlyHint=true, idempotentHint=true, openWorldHint=false and destructiveHint=false, so the safety profile is covered. The description adds genuine context beyond that: it discloses that results are assembled from two sources (USDA PSD for balances, UN Comtrade for values/suppliers) and enumerates the derived metrics returned, which is important since there is no output schema.

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?

A single dense sentence front-loads the core output set before the commodity list, and every clause carries information (metrics, sources, coverage) rather than filler. It reads as a run-on, but nothing is redundant enough to cut.

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 and only one documented parameter, the description carries the return-value burden and does so by listing the metrics and their provenance. Gaps remain around temporal range (which years are available) and result granularity, but an agent can form a correct call from what is given.

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 only 33% (only 'product' is documented), so the description must compensate, and it does: it supplies the supported commodity vocabulary and constrains 'country' to Central America, complementing the enum. It does not explain the language parameter's effect on returned text or map the English commodity names to their Spanish equivalents, so the compensation is partial.

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 names the resource concretely (supply balance: production, imports, exports, consumption, import share, self-sufficiency, market value, suppliers) and its scope (staple commodity, Central American country), and it names the two underlying sources (USDA PSD, UN Comtrade). It does not explicitly contrast itself with near-neighbors such as trade_by_product, find_suppliers, or search_prices, so overlap must be inferred.

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?

Usage is implied rather than stated: the agent can infer this is for country-level supply/self-sufficiency questions about listed staples, but there is no explicit when-to-use, no when-not-to-use, and no pointer to an alternative tool for adjacent questions like bilateral trade flows or price lookups.

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