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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so safety is covered. The description adds only that the response language is selectable, which is genuinely useful behavior context, but says nothing about what the fiche contains or how missing records behave.

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 compact sentence with the resource front-loaded and the identifier alternatives attached directly to the key parameter. The telegraphic 'langue : fr, en, …' tail is efficient rather than padded.

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?

No output schema exists, so the description would ideally sketch the shape of a 'fiche complète' (which fields come back). It covers inputs adequately for a two-parameter read tool but leaves the return content entirely unspecified.

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 0%, so the description must carry the parameter burden and it largely does: it clarifies that 'identifiant' accepts either an 'id' field or a SIRET, and it enumerates the accepted 'langue' values (fr, en, es, de, it, zh) that the schema does not encode as an enum. It stops short of explaining whether language affects only the output text.

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 (retrieve) and resource ('fiche complète d'un établissement') with the two supported lookup keys. It implicitly contrasts with the sibling search tool 'rechercher_imprimeurs' by emphasizing that this is a full record fetched by identifier, though no sibling is named explicitly.

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?

The phrasing 'par son identifiant ou son SIRET' implies the caller already holds a key, which differentiates it from a search flow, but it never states when to prefer 'rechercher_imprimeurs' to obtain that key first, nor any failure case for an unknown identifier.

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