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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=false, so safety is covered; the description adds real behavioral context on top: cycle detection in dependencies, end date computed from start, comparison against a contractual deadline, and the 'indicatif / jours calendaires' caveat that qualifies the accuracy of results.

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?

One dense paragraph, front-loaded with the when-to-call clause followed by outputs, input shape, and caveats. Efficient, though the run-on enumeration of outputs makes it slightly harder to scan than a short structured list would be.

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?

There is no output schema, and the description compensates by naming the exact result fields (ES/EF/LS/LF, marges, chemin critique, retard). Combined with the input-shape and default-source notes, an agent has enough to call it correctly, with only sibling disambiguation left unaddressed.

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 schema already documents all four parameters, and the description mostly restates them (task tuple shape with optional jalon, ISO AAAA-MM-JJ for debut and date_limite, default fallback to scene). The default-task-resolution behavior is the main value-add, but nothing is added on validation, required task fields, or how dependencies are matched by name.

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 (ordonnancer) and resource (chantier) plus the method (chemin critique, 4D avance) and enumerates the computed outputs (ES/EF/LS/LF, marges, chemin critique, retard). It does not, however, differentiate itself from the near-identically named siblings cao_bim_4d_cpm, cao_4d and cao_bim_4d5d, which an agent could easily confuse with it.

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 ordonnancer le chantier par la METHODE DU CHEMIN CRITIQUE' gives an explicit trigger condition, and the default source of tasks (scene.taches_personnalisees, sinon taches 4D de la scene) is spelled out. There is no exclusion or explicit pointer to an alternative tool for non-CPM scheduling.

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