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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is fully covered by structured data. The description adds only that the result is a paginated list, which is modest extra context; it says nothing about result ordering, empty results, or the default page size.

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?

A single front-loaded sentence: purpose, domain, search dimensions, and return shape, with zero filler. Nothing could be removed without losing information.

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 five-parameter, no-required-parameter search tool with no output schema, the description covers the essential behavior and return type. It stops short of noting that all filters are optional or how the filters combine, which an agent would need for confident multi-filter calls.

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 every parameter is already documented in the schema (including the enum for type and the prefix example). The description's mention of texte/type/préfixe mirrors those parameters without adding syntax, defaults, or interaction rules, 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?

The description states a specific verb (Rechercher) and resource (numéros spéciaux français dans l'annuaire Losali), plus the search dimensions (texte, type, préfixe) and the paginated return. It is clear on its own, but never names or distinguishes itself from the sibling get_number, which also deals with numbers.

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 only implied: an agent can infer this is the multi-result lookup and get_number is the single-record lookup, but the description never says when to prefer search over get_number, nor when to combine q/type/prefix. No exclusions or alternatives are stated.

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