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

Annotations already declare readOnlyHint, idempotentHint, non-destructive, and closed-world behavior, so the safety profile is covered. The description adds the return keys {per_load_eur, weekly_eur, annual_eur}, but since an output schema exists this is largely duplicative rather than new behavioral context.

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 front-loaded with the core action and result, uses two short sentences plus a pointer, and contains no filler. Every sentence adds useful information for an agent.

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 simple, deterministic calculator with rich annotations, full schema coverage, and an output schema, the description provides enough context to invoke it correctly. The only minor gap is explicit guidance on when to choose it over nearby cost calculators.

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 each parameter is already documented with type, default, and description. The description's mention of electricity, water, and detergent maps conceptually to the parameters but adds no syntax, constraints, or defaults beyond the schema, matching the baseline for fully covered 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 states a specific verb (Calculate) and resource (weekly and annual laundry cost), and it enumerates the cost components (electricity + water + detergent). This clearly differentiates it from generic electricity, water, or detergent calculators in the sibling list.

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?

It points to list_bundles for related 'vie-quotidienne' calculators, which gives some discovery guidance. However, it does not state when to use this tool instead of alternatives like calculate_electricity_cost or calculate_water_bill, leaving usage selection largely implied.

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