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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is covered without description help. The description does add genuine value beyond the annotations by warning that street/commune counts do not prove publication or indexing of the corresponding pages, which shapes how results should be interpreted. It does not, however, describe operational behavior such as filtering by city_id or how the optional parameter affects the payload.

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?

Two compact sentences with no filler, and the resource scope is front-loaded before the interpretive caveat. The noun-phrase style is slightly elliptical but efficient; nothing is redundant enough to warrant trimming.

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?

An output schema exists, so return-value structure need not be restated, and the annotations cover the safety profile. What remains missing is any explanation of the single city_id parameter and any condition for choosing this tool over search_communes or get_street_context, leaving the definition adequate but incomplete for invocation decisions.

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 0% and there is one parameter (city_id), so the description carries the burden of explaining it — yet it never mentions city_id at all. The regex pattern hints at a French postal code or Corsican 2A/2B code, but nothing explains whether omitting the optional parameter returns national coverage versus a city-scoped subset. This is a meaningful gap for an optional filter parameter.

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 set: the scope of the national Callejear.fr catalog, data definitions, collection gaps, and source limitations. That distinguishes it from the street/commune siblings, which focus on entities rather than catalog metadata. It loses a point for being a bare noun phrase with no action verb ('Périmètre du catalogue...'), so the agent must infer that the tool returns this information rather than performing something 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?

There is no guidance on when to call this tool, when not to, or which sibling to prefer for a given need. The second sentence is an interpretive caveat about counts, not a usage condition. An agent must guess that this is the right tool for catalog-metadata questions rather than getting an explicit trigger.

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