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

Annotations already declare this a safe, non-destructive, non-open-world read, so the bar is lower. The description nevertheless adds genuine behavioral commitments beyond them: views are printed at TRUE SCALE ('never a false one'), every sheet carries a title block with revision table and an 8-character model fingerprint, and the exact return shape is described.

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 WHEN trigger, then the sheet composition, then the scale policy, then the return shape. Dense but every sentence carries information an agent needs. The single long paragraph hurts scannability slightly, blocking a 5.

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 13-parameter, nested-object tool with no output schema, the description closes the important gaps: it explains what is produced, the scale guarantee, the contents of the title block, and the exact JSON return ({feuilles, empreinte, html}). Nothing an agent needs to invoke it correctly is missing.

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% across 13 parameters, and each field is documented in the schema itself (units, defaults, frame conventions). The description adds no parameter-level guidance of its own, so the baseline of 3 is appropriate.

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 states a concrete verb and resource: it 'builds numbered A3 or A1 sheets' with an enumerated sheet set (cover, site plan, plans per storey, elevations, section, MEP plans, schedules). That is far more specific than the title alone. It does not, however, name any sibling (e.g. cao_pdf or cao_generer_dxf) to sharply delimit its scope, so it falls short of a 5.

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?

A clear WHEN clause ties the tool to a real decision point: issuing a design as a drawing set for a client, a planning application, or a contractor. It gives context but no exclusions and no named alternative (e.g. when to reach for cao_pdf instead), which is the remaining gap.

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