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

Annotations already declare readOnlyHint=true and destructiveHint=false, and the description confirms 'Lecture seule' while adding genuinely new context: the result is indicative only, with authoritative references (DTU 20.1, signed structure note) taking precedence. It does not describe the response shape, but with no output schema and safe-read annotations that is a minor gap.

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 dense sentence front-loads the trigger, then the checklist with IDs, then the input shape and the caveat. Nothing is wasted, and the enumeration maps one-to-one onto the checks performed.

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?

Given one optional nested parameter, read-only annotations, and no output schema, the description supplies the trigger, the checklist, the input shape, and the authority caveat. The only missing piece is any hint about what the check returns, which is minor here.

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 parameter already documents the nested vide_sanitaire object; the description merely repeats the same field list (hauteur_cm, ventilation, acces, drainage). It adds no format, unit, or default guidance beyond the 20 cm threshold mentioned for the height check.

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 (VÉRIFIER) and resource (le vide sanitaire) and enumerates the exact criteria checked, each with an identifier (VS-HAUTEUR, VS-VENTILATION, VS-ACCES, VS-DRAINAGE). No sibling in the large cao_bim_* family covers crawl spaces, so the agent can route to it unambiguously.

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?

Opens with an explicit trigger condition ('Appelez quand vous devez VÉRIFIER LE VIDE SANITAIRE') and adds a scope caveat that the DTU 20.1 and the signed structural note take precedence. It does not name an alternative tool for cases where this one is not the right fit, which keeps it below a 5.

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