emissions_calculator

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

Annotations already indicate read-only, idempotent, non-destructive behavior, and the description adds substantial behavioral detail beyond that: deterministic results, built-in empty running, low representativeness for sea/air, unknown inputs returning available:false rather than fabricated factors, and rate-limiting behavior with 429 handling. The description is fully consistent with 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 long but every sentence earns its place. It front-loads the core formula and required inputs, then adds important parameter guidance, behavioral notes, return-envelope content, limitations, and sibling-tool distinctions. It is well-organized into functional paragraphs with no fluff or tautology.

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?

Given 7 parameters, an output schema, and a rich context from sibling tools, this description is complete: it covers input requirements, key parameters, edge cases (unknown returns, rate limits), the return envelope, limitations, and explicit distinction from related calculators. An agent has everything needed to select and invoke the tool correctly without external guesswork.

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?

Although schema descriptions cover all 7 parameters, the tool description adds critical semantic nuance: actual gross mass vs chargeable/volumetric weight (a common air-freight mistake), the fact that distance is caller-provided with no routing behavior, the meaning of wtw vs ttw, and region/authority mappings (uk=DEFRA, us=EPA, fr=ADEME). This goes well beyond the schema's short field descriptions.

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?

Description opens with a specific verb and resource: 'Estimate freight transport greenhouse-gas emissions (kgCO2e) for a shipment leg' per ISO/GLEC standards. It clearly defines the calculation formula and the required inputs. The closing line distinguishes it from cbm_calculator, ldm_calculator, and chargeable_weight_calculator by stating those size/bill a shipment while this one estimates CO2e.

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?

Explicitly instructs when to use the tool and with what care: pass actual gross mass not chargeable weight, provide distance because the tool does not route, and do not add an empty-return leg. It also names sibling calculators that are distinct and directs to get_subscribe_link for higher rate limits. This is full usage guidance with both affirmative and exclusionary conditions.

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