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

The annotations already declare the full safety profile (readOnly, idempotent, non-destructive, closed-world), so the description is not the primary carrier here. It adds that results include HT, TVA and TTC amounts plus totals, which is useful but largely overlaps the existing output schema.

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?

Two sentences, no filler, with the searchable dimensions front-loaded and the return payload named last. Nothing in it is redundant padding.

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 an output schema present and annotations covering safety, the description only needs to frame the search surface and return shape, which it does. It omits how multiple filters combine and the relevance/ordering default, but the rich schema and output schema limit the practical gap.

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 one of the 16 parameters is already documented with type, format examples and defaults. The description's enumeration of searchable fields mirrors the schema rather than adding syntax or combination semantics (e.g. whether filters are ANDed).

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 and resource ('Recherche des factures') and enumerates the searchable axes (numéro, période, client, société, montant, produit, lieu de facturation), which makes clear this is a flexible query rather than a single-invoice lookup. It does not explicitly contrast itself with the singular sibling get_invoice, so it falls just short of full sibling differentiation.

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 search_orders, search_customers, or get_invoice, and no mention of prerequisites or when results might be empty. Usage must be inferred entirely from the name and parameter list.

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