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

Annotations already declare readOnly/ idempotent/non-destructive, so the safety profile is covered. The description adds real behavioral context beyond that: it discloses the structure of retour for EHPAD results (offre_hebergement with places, habilitation, prix CNSA, HAS quality class). It does not discuss pagination or limits behavior, keeping it at 4.

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?

Front-loads purpose before modes, then uses parentheses and a numbered list for the two search strategies. The closing EHPAD paragraph on retour fields is dense but informative rather than redundant, so little is wasted.

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 6 parameters, 100% schema coverage, no output schema, and read-only annotations, the description supplies everything needed: the resource, the two modes, the relevant filters, and a substantive sketch of what results contain for the key use case (EHPAD).

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 goes further by explaining the relationship between radius_km and search mode and by motivating the alzheimer and aide_sociale filters, adding selection logic that the raw schema entries state only individually.

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 specific verb ('Recherche') and resource ('etablissements de sante dans la base FINESS'), enumerates the covered establishment types, and lays out two distinct search modes. An agent instantly knows this is a FINESS facility lookup and can tell it apart from territory-analysis siblings like analyze_territory and compare_territories.

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?

Gives explicit when-to-use guidance for the proximity mode: 'Utilise radius_km quand l'utilisateur demande les etablissements les plus proches... dans un rayon de X km', and clarifies the default administrative-limits mode. No explicit when-not or named alternative tool, but the mode-selection context is clear.

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