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

With no annotations, the description carries the full burden. It transparently discloses that the catalogue is free (no API key, 0 units), details the return structure ({categorie, libelle, cotes_defaut}), explains that dimensions are optional with real commercial defaults, clarifies placement semantics (z is floor level), and states where results appear (4K visit, PDF, DXF, quantities). This goes beyond basic functionality to cover important behavioral nuances.

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?

The description is long but well-structured, front-loading the primary purpose and using a categorized list to convey the catalogue contents. Every sentence adds value, though a tighter organization could reduce overall length while maintaining clarity.

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 tool with no parameters, no output schema, and no annotations, the description is remarkably complete. It covers purpose, usage context, return format, placement rules, integration with other outputs, and deduplication constraints. No critical information appears missing or ambiguous.

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?

The tool has zero parameters, so the baseline for parameter semantics is 4. The description adds context about optional dimensions and the placement object ({type, x, y, z, rotation}) that will be used with the returned data, which is meaningful and compensates for the empty schema.

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 clearly states the tool's function: it provides a free catalogue of real furniture and decoration objects for furnishing scenes. It uses a specific verb ('call this BEFORE composing mobilier[]') and resource, and explicitly distinguishes it from the alternative boites[] (bare cuboids). The scope is well-defined with item categories.

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?

The description gives explicit when-to-use guidance: 'WHEN you are about to furnish or decorate a scene—call this BEFORE composing mobilier[]'. It also provides a clear exclusion: 'never furnish with boites[]' and advises not to duplicate plumbing fixtures already in plomberie[]. This sufficiently differentiates from alternatives.

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