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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so the safety profile is covered. The description adds value by listing the payload contents, including an external link, but says nothing about not-found behavior, whether the name match is fuzzy or exact, or the response shape.

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?

One front-loaded sentence that spends its words on the returned fields rather than restating the title. The field enumeration is long but each item earns its place by telling the agent what the sheet contains.

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 one required parameter, rich annotations and no output schema, the description does the main remaining job by enumerating the returned metrics. The only meaningful gap is edge-case behavior, e.g. what happens when the supplied name matches no SCPI or matches several.

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% and the single parameter already documents both name and identifier with examples ('Transitions Europe', 'iroko'). The description adds no further semantics about accepted formats or matching tolerance, 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 and resource ('Renvoie la fiche chiffrée d'une SCPI') and enumerates the returned metrics (prix, taux de distribution, capitalisation, frais, dernier bulletin), so the agent knows exactly what data this yields. It does not, however, contrast itself with siblings such as rechercher_scpi or comparer_scpi, which also operate on SCPIs.

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: the agent must infer this is the tool for pulling a full detail sheet on one identified SCPI. There is no explicit when-to-use versus rechercher_scpi (search) or comparer_scpi (comparison), and no stated prerequisites or exclusions.

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