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

Annotations already declare readOnlyHint, idempotentHint, non-destructive and non-open-world, so the safety profile is fully covered. Because there is no output schema, the description's enumeration of returned content (code, benefits, condition, payment delay, verification date, official page) adds genuinely useful behavioral/output context. It omits auth/data-freshness caveats but does not need to repeat the annotation-covered traits.

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 that puts the verb and resource first. The trailing field enumeration is long but each item earns its place by previewing the return content in the absence of an output schema. Slightly heavy but no wasted framing.

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 read-only, idempotent, single-parameter detail lookup, the description is nearly complete, and notably it compensates for the missing output schema by listing returned fields. The only gap is the lack of explicit routing guidance relative to siblings.

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 "marque" parameter is documented with examples, so the schema carries the semantics. The description adds no syntax, format, or matching-behavior detail beyond what the schema provides, which is the expected baseline.

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 uses a specific verb ("Renvoie") and resource ("la fiche complète d'une marque"), so an agent can tell this is the detail/retrieval tool versus list-oriented siblings. It enumerates the returned fields, reinforcing what "detail" means. It does not, however, explicitly distinguish itself from siblings like rechercher_offres or meilleures_offres.

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: returning the "fiche complète" suggests this is the tool for full per-brand details once a brand is known. There is no explicit when-to-use, when-not-to-use, or named alternative among the five siblings. The agent must infer the routing.

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