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

Annotations already declare readOnlyHint, openWorldHint and destructivenes=false, so the safety profile is covered. The description goes further and adds genuinely new behavior: no calculation is performed, no amount is returned, and payment happens externally on the site – which prevents the agent from expecting a price. No rate limits or resolution/precondition details are given, but the added context is substantive.

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 key behavior (returns the service-page URL) is front-loaded, and the two closing sentences are tight and high-value. But the opening sentence embeds a long parenthetical list of thirteen professions that the input schema already enumerates, adding length without new 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?

With an output schema present, return values need not be described, and annotations cover the safety profile, so the remaining burden is light. The description covers the input interpretation, the fallback branch and the no-payment behavior. The only gap is explicit disambiguation from the four similarly named sibling tools.

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 the baseline is 3, and the profession enumeration in the description largely duplicates the schema's 'Valeurs typiques' list. What it adds is the interpretation rule for unmatched free-text input: an individual or unlisted profession is routed to the professional pricing page, which is real semantic guidance on how the parameter is resolved.

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 gives a specific verb and resource: it takes a prospect's profession and returns the URL of the corresponding HEL service page. It even enumerates the supported professions and the fallback (particulier/non listée → page tarifs professionnels). It never names or contrasts a sibling tool, so an agent must infer the boundary with hel-tarifs-abonnements or hel-orienter-commande on its own.

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?

Clear context for use: when you have a prospect's profession and need the matching service page. It also handles the edge case (particulier or unlisted profession → professional pricing page), which is effectively a when-to-use branch. However, no alternative tool is ever named, so the routing decision against the four sibling tools is left implicit.

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