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

Annotations already declare readOnly/idempotent/non-destructive/openWorld=false, so the safety profile is covered structurally. The description adds little beyond that – it notes it 'returns total emissions and breakdown,' which is largely redundant given an output schema exists, and omits any assumptions or limits of the estimate.

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?

Five short, front-loaded segments with no filler; the purpose and unit lead. Slightly list-like with 'Inputs:' and 'Returns:' fragments, but nothing is wasted.

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 an idempotent read-only calculator with a full output schema and 100%-documented params, the description covers purpose, inputs, return shape, and related tools. Only the lack of guidance on estimate assumptions/limits keeps it from being fully 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 100%, so the four parameters (kwh, km_car, km_plane, meat_kg_week) are already documented. The description's 'housing, transport, diet, lifestyle' summary loosely maps to them but adds no syntax, units, or defaults beyond the schema, so baseline 3 applies.

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?

States a specific verb (Estimate) and resource (annual personal carbon footprint) with a unit (tCO₂e). Clear and self-contained, but it does not distinguish itself from the similarly named sibling calculate_carbon_sequestration, which an agent scanning the tool list could confuse.

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?

'Use for sustainability awareness' implies a context but gives no when-to-use/when-not guidance or named alternatives. The pointer to list_bundles for 'vie-quotidienne' calculators hints at related tools but is not a routing rule for picking this tool over siblings.

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