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

Annotations already declare readOnly, idempotent, and non-destructive behavior, so the bar is lower. The description adds value by specifying the return content ('Renvoie ses métiers, sa ville, sa note, sa description et le lien de sa fiche izifete.fr') and the prerequisite that the ID must come from a prior search. No contradictions with annotations.

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 concise, using three sentences that each serve a purpose: when to use, what it returns, and exclusions. It is front-loaded with the main usage directive and contains no filler or unnecessary details.

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 the tool's simplicity (1 parameter, no output schema), the description is complete: it explains the input source, return fields, and exclusions, and is aligned with annotations. There are no significant gaps for an agent to misuse this tool.

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?

The schema already fully describes the only parameter 'id' with the description 'Identifiant du prestataire renvoyé par search' (100% coverage). The tool description repeats this same information ('à partir de son identifiant obtenu via search'), adding no new meaning beyond the schema, so baseline 3 is appropriate.

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 states that this tool fetches details of a specific Izifete provider using an ID from search: 'Utilise cet outil quand l'utilisateur veut les détails d'un prestataire Izifete précis, à partir de son identifiant obtenu via search.' It explicitly distinguishes itself from sibling tools by excluding search (search) and request creation (creer_demande).

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 explicit when-to-use guidance ('quand l'utilisateur veut les détails d'un prestataire précis') and when-not-to-use guidance ('N'utilise PAS cet outil pour rechercher plusieurs prestataires (search) ni pour envoyer une demande (creer_demande)'), clearly differentiating from alternatives.

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