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

Annotations already indicate read-only, idempotent, open-world, non-destructive behavior. The description adds meaningful behavioral detail: output distinguishes universally required pieces from terrain-triggered ones, and facts are based on commune center rather than a specific address. This exceeds annotation coverage.

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?

A single, dense sentence carries the full purpose, scope, output categorization, and spatial limitation without redundancy. Every clause earns its place, and key information is front-loaded.

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 simple one-parameter, read-only tool with no output schema, the description covers purpose, scope, granularity, and categories of results. It does not enumerate the actual pieces, but that is not required for tool selection; the description is reasonably complete for invoking the tool correctly.

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 baseline is 3. The description adds value by explaining that code_insee determines commune-level triggers like sismicite, risk prevention plans, and historic monuments, and clarifies spatial resolution (commune center). This goes beyond the schema's format-only description.

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 resource ('pieces a joindre a une demande de permis de construire pour une maison individuelle'), specifies the Cerfa form, and distinguishes universal requirements from terrain-triggered ones. This clearly differentiates it from the urbanism-rule siblings.

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 makes the context clear: it is for an individual house building permit in France, with results read at commune center, not at an address. It implicitly excludes address-level use but does not explicitly name alternatives or state when-not-to-use relative to the sibling tools.

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