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

Annotations already declare readOnlyHint=true and destructiveHint=false, yet the description goes well beyond them: it clarifies the link is opened and sent by the user, that transport carries a study fee distinct from the transport price, and names the response fields ('avis_frais', 'a_dire_a_l_utilisateur'). The closing 'creates nothing and charges nothing' directly confirms and enriches the safety profile.

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 core action and return value are front-loaded in the first sentence, followed by per-service fee behavior and a closing safety statement. Every sentence carries distinct information with no filler or redundancy.

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 request-preparation tool with 8 well-documented parameters and no output schema, the description supplies what the schema cannot: the fee implications per service and the names of the fields returned. An agent has everything needed to invoke it and set expectations for the user.

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 coverage is 100%, so the baseline sits at 3, but the description adds real meaning beyond the schema by tying the 'service' enum values to fee consequences and by surfacing the response fields that carry the fee information. The remaining parameters (date, depart, arrivee, quantite) receive no elaboration beyond their schema 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?

The description states a specific verb and resource ('Prepares a request to GraceRoad and returns a link for the user'), which is inherently distinct from the informational siblings graceroad_corridors and graceroad_presentation. It never names or contrasts those siblings explicitly, so it stops short of the top mark, but the purpose is unambiguous.

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 explains the outcome and cost profile for each service value ('transport' carries a study fee, 'carburant' offer is free, 'sourcing' enquiry free with fixed fee after), which helps an agent pick the right service. However, it gives no explicit when-to-use guidance against the sibling tools or any exclusions, so usage is implied rather than stated.

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