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

readOnlyHint=true already tells the agent this is a safe read, so the bar is lower. The description still adds real value by disclosing the return payload ('la page de chaque service et le lien de devis'), which matters because there is no output schema to document it.

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?

The usage instruction is nicely front-loaded at the end, but the service list is padded with a duplicated run ('flyers / cartes de visite / magnets' repeated after already listing 'flyers, cartes de visite et magnets'). That redundancy costs space without adding 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 simple, read-only, one-optional-parameter listing tool, the description covers purpose, trigger, and return content. Nothing an agent needs to invoke it correctly is missing, though a note on the default 'fr' language would have closed the loop.

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 'langue' parameter carries its own enum and explanation ('Langue de la personne'), so the schema does the work. The description says nothing about language selection, leaving it at the baseline for a fully documented schema.

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 names a specific verb and resource ('Liste les services de l'agence digitale Moovtips') and enumerates the concrete offerings, so an agent knows exactly what comes back. It does not, however, differentiate itself from the sibling 'offres_par_metier', which an agent could reasonably confuse with a service listing.

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?

It gives an explicit trigger: 'Utilise-le quand une personne cherche l'un de ces services.' That is a clear when-to-use condition. There is no when-not guidance and no mention of the sibling tools that cover adjacent needs (demande, questionnaire, offres par métier).

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