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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=false, so 'Lecture seule' is redundant; however 'Indicatif — dimensionnement NF EN 13141 signe prime' adds genuine value by warning that results are non-normative and a signed sizing remains authoritative. The numeric acceptance threshold (>= 80 % recovery) is also useful context. It does not say what the response per check looks like, but no output schema exists to cover that.

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 invocation trigger, then the acceptance criteria, then the input shape and the caveat — a sensible order with no filler. The scene field list partly repeats the schema, which is the only wasted space in an otherwise tight paragraph.

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 optional-parameter, read-only verification tool with no output schema, the description supplies the check list, the thresholds, and the non-normative disclaimer. The remaining gap is what the tool actually returns per check (pass/fail, values), which the agent must discover by calling it.

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?

With a single parameter and 100% schema description coverage, the schema already documents the nested 'double_flux' object and its keys. The description restates the same key list, adding only a light mapping between reference codes (DF-RENDEMENT) and field names (rendement_pct); qualifying baseline 3 applies.

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 and resource ('VERIFIER LA VMC DOUBLE FLUX') and enumerates the four checks it performs with their reference codes (DF-RENDEMENT, DF-ETANCHEITE, DF-BYPASS, DF-FILTRES). It is clearly scoped to heat-recovery ventilation, distinguishing it implicitly from cao_bim_vmc and cao_bim_ventilation_naturelle, but never names those siblings to route the agent explicitly.

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...' gives an explicit invocation trigger tied to a concrete engineering task. It stops short of stating when NOT to use it or which sibling to pick for related ventilation checks, leaving that inference to the agent.

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