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

Annotations already declare readOnlyHint=true and destructiveHint=false, so 'Lecture seule' adds nothing new. The valuable, non-redundant disclosure is 'Indicatif — reglementation assainissement et CCTP signes priment', which tells the agent the results are advisory and may conflict with signed documents — a behavioral trait no annotation conveys. It still says nothing about what a check produces (findings vs. booleans) or the granularity of the four criteria.

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?

Front-loaded with the action verb and the check dimensions, which is exactly the right ordering. Slight waste in re-declaring 'scene : microstation {emplacement, traitement, rejet, entretien}', which duplicates the input schema verbatim and could have been spent explaining what each sub-check evaluates.

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 no output schema, the description carries the burden of indicating what comes back, and it does not: the agent knows four aspects are examined but not the form of the verdict (per-point conformance, missing elements, textual findings). The indicative-vs-normative caveat helps, but a verification tool whose return shape is unstated leaves a real gap.

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 there is a single nested 'scene' parameter, so baseline is 3. The description restates the same sub-keys {emplacement, traitement, rejet, entretien} already present in the schema and adds no further detail on the shape or expected content of those nested objects, nor how scene data is interpreted during the 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?

The description names a specific verb ('VERIFIER') and resource ('MICROSTATION / assainissement autonome') and enumerates four checked aspects (emplacement, traitement, rejet, entretien) with codes. The scope is unambiguous. It stops short of distinguishing itself from the many adjacent wastewater siblings (cao_bim_assainissement, cao_bim_eaux_usees, cao_bim_evacuation, cao_bim_raccordement_egout), leaving the agent to infer that this one is specific to packaged microstations.

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?

'Appelez quand vous devez VERIFIER LA MICROSTATION' is an explicit invocation trigger, and the four listed dimensions clarify what qualifies as an in-scope check. The caveat 'reglementation assainissement et CCTP signes priment' signals the output is not authoritative, which functions as a soft when-not-to-rely. No named alternative tool is given, so it falls short of a full 5.

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