Urbanism rules at an address (PLU)

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

With no annotations, the description carries the full burden of behavioral disclosure. It adds value by clarifying that the tool only states applicable rules and never judges project permission, a key behavioral boundary. It also cites the data source (GPU, DGALN / IGN), lending confidence about provenance. It does not mention read-only nature or error behavior, but the boundary is a solid extra beyond the basic purpose.

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 two well-structured sentences. The first sentence delivers the core purpose and lists the output components; the second adds the crucial limitation and the source. There is no filler, and the caveat is positioned for impact. It earns every word.

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?

Given there is no output schema, the description appropriately explains what the tool returns (zoning label/type, document reference, prescriptions). It also gives the source and the non-permission boundary. It does not cover coordinate format or edge cases like missing data, but for an agent deciding whether to call the tool and understanding its output, this is largely sufficient.

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 only 33% (only 'address' has a description). The tool description does not compensate for the undocumented 'lat' and 'lon' parameters—it does not specify coordinate format, reference system, or whether they are alternatives to address. The description mentions 'address' but adds no further parameter meaning. This leaves a significant gap for an agent needing to correctly populate coordinates.

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 identifies the specific resource: urbanism zoning and prescriptions applicable to an address. It enumerates the returned information (zoning type, document reference, prescriptions) and implicitly distinguishes itself from sibling tools focused on property value, sales, and risks. This is more than sufficient for an agent to recognize the tool's unique purpose.

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 provides an explicit exclusion: 'never whether a project is permitted,' which signals when not to use this tool. It also sets context by mentioning the Géoportail de l'urbanisme source and address-based usage. However, it does not name any alternative sibling tool or explicitly state 'use this when you need zoning rules.' Thus it stops short of full routing guidance.

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