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

Annotations already declare readOnlyHint/destructiveHint=false, and the description reinforces this with 'Lecture seule'. It adds genuinely useful behavioural context beyond the annotations: the check is 'Indicatif' and professional rules / manufacturer notices prevail, which tells the agent how to weight the result. It does not describe the shape of the returned verdict (list of non-conformities vs. pass/fail), which keeps it from a 5.

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 trigger comes first, then the rule set, then the schema hint, then the caveat — a sensible front-loaded order. It is dense but every clause carries a threshold or a constraint; only the schema restatement is partly redundant with the input schema.

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 single-parameter, read-only checking tool with no output schema, the description supplies all the domain rules and the caveat needed to invoke it and interpret it responsibly. Only the nature of the returned diagnostic (per-item compliance report?) is left unstated.

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 nested 'scene' object is fully spelled out in the schema itself. The description restates the same field list (nom, ossature, lame_air_mm, pare_pluie, fixation, jeu_pied_mm, joint_dilatation_m) without adding units conventions, defaults, or how missing fields are handled. Baseline 3 is appropriate when the schema does the work.

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 ('verifier') and resource ('BARDAGE RAPPORTE') and enumerates exactly what is checked (lame d'air >= 20 mm, pare-pluie, ossature/fixations, jeu en pied, joints de dilatation). This differentiates it clearly from neighbours like cao_bim_etancheite, cao_bim_toiture_terrasse or cao_bim_charpente, which cover different envelope elements.

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?

The opening 'Appelez quand vous devez verifier un BARDAGE RAPPORTE' gives an explicit trigger condition. It does not name a sibling alternative or state when not to use it, so it falls short of a 5.

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