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

Annotations already declare readOnly/idempotent/closed-world, so the safety profile is covered. The description adds genuinely non-obvious behavior: rows with ambiguous or unresolvable codes return an "options" field of candidate communes with their département instead of indicators, which changes how an agent must handle the response.

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 first sentence is dense and front-loaded with the essential contract, including the error/fallback shape. The second paragraph is provenance and licensing metadata; it is short and arguably relevant to non-commercial use, but it is the least load-bearing part of the text.

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?

With no output schema, the description carries the burden of describing the return shape and does so, including the alternate "options" response. Data vintages (RPG 2025, BNVD 2024) help interpretation; only row ordering/field naming details are left unstated.

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% and the single parameter already documents 2–5 INSEE codes or slugs, so the description's "Codes = INSEE ou slug" is essentially a restatement. It adds only the connection between code ambiguity and the fallback output, not new parameter semantics.

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?

States a concrete output (aligned comparison table) over a specific resource (2 to 5 communes) with named indicators (exposition, parcelles, bio, écoles, achats BNVD). This is clearly distinct from single-commune siblings like get_commune_exposure or get_school_proximity, though no sibling is named explicitly.

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 2–5 cardinality and accepted code formats are stated, and the ambiguous-code fallback is described, but there is no explicit guidance on when to pick this over rank_communes or the per-indicator tools. Usage is implied by the shape of the output rather than stated.

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