Compare CBAM default values across origins

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

Annotations cover the safety profile (readOnly, idempotent, non-destructive), so the bar is lower. The description adds meaningful context beyond annotations: the 30-country cap, inclusion of the 'Other countries and territories' row and Annex IV value, units (tCO2e per tonne), the legal caveat (Excel values not legally binding; the binding source is named), and that provenance/fallback rules are surfaced. It does not describe output format or pagination, but this is a comparison listing, so that gap is modest.

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 a single dense sentence packing the 30-cap, special rows, units, legal caveat, and provenance behavior — front-loaded with the core purpose but burdened with parenthetical legal detail that partly competes with the main action. Efficient but somewhat overloaded.

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 two-parameter read-only comparison tool with no output schema, the description supplies the essential domain context: scope (one CN code, several origins), special rows included, units, and the legal non-binding caveat with a pointer to the binding regulation. It does not specify return structure, but the comparison intent is adequately conveyed.

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 coverage is 100%, so the schema documents cn_code formats and the countries array with max 30. The description does not restate parameter syntax, but it reinforces the max-30 constraint and clarifies that origins are shown 'side by side', which frames how the countries array is used. Given the high schema coverage, this is above the baseline 3.

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 states a specific verb (compare side by side) and resource (CBAM default values of a CN code across countries of origin). It is reasonably distinguishable from siblings like default_value (single value) and sources, though it does not explicitly name or contrast against those siblings.

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 by the tool's purpose (comparing multiple origins at once, up to 30), but the description never explicitly states when to use this versus default_value for a single origin, nor when-not to use. No exclusions or alternatives are named.

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