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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=false, so the safety and repeatability profile is fully covered without the description. The description adds only the output field list, which is largely duplicative of the declared output schema rather than new behavioral context such as input constraints or calculation assumptions (e.g. what the 'ancien' vs 'neuf' rate treatments imply).

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?

Three short, front-loaded clauses: purpose, returned fields, and a cross-reference. Nothing is wasted, though the enumerated return fields partly restate an output schema that already exists, which is slight redundancy rather than bloat.

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 a declared output schema and full annotation coverage, the essential burden on the description is selection and scope, and it does state the domain and the purchase context. The meaningful gap is disambiguation from 'calculate_notary_fees_detailed' and other property-fee siblings, which is unaddressed.

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%: both 'price' (euros, min 1) and 'type' (ancien/neuf enum with default) are documented in the schema. The description adds no additional parameter meaning or format detail beyond what the schema already supplies, so the baseline of 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 ('Calculate'), a specific resource ('French notary fees (frais de notaire)') and the scope ('for a real estate purchase'), which is unambiguous on its own. However, it does not distinguish itself from the closely related sibling 'calculate_notary_fees_detailed', so an agent cannot tell which of the two to pick from the description alone.

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?

There is no statement of when to use this tool versus the near-identical 'calculate_notary_fees_detailed' sibling, nor any prerequisite or eligibility note. The only routing hint is to 'list_bundles for related finance-france calculators', which is a catalog pointer, not guidance on selecting this tool for a task.

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