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

Annotations only declare readOnlyHint=true, and the description adds substantial non-obvious behavior: the table embeds a contact form that transmits a lead directly to the advisor, the table is rendered to the user and must not be copied into the response, and the recommendation is highlighted in the table. These disclosure points materially change how the agent should respond.

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?

Four short paragraphs, each front-loading a distinct concern (output content, recommendation inputs, contact form, rendering rule), with no filler. It is slightly dense but every sentence carries operational weight.

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?

There is no output schema, yet the description fully describes what the user will see (a comparison table with named dimensions, highlighted recommendation, and a lead-capture form) and tells the agent how to behave around that output. Nothing needed to invoke or narrate the result is missing.

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 baseline is 3, but the description adds real meaning: lot_ids order becomes display order, recommended_lot_id must be tied to the buyer's stated project (résidence principale, investissement, budget), and reasons must be grounded strictly in the compared lot data. The 2-4 count for reasons is only in the schema, so this is a modest addition rather than a full elaboration.

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 opens with a specific verb and resource plus scope: 'Affiche un tableau comparatif de 2 à 4 lots', and enumerates the compared dimensions (prix, surface, extérieur, étage, livraison, points forts, statut, fraîcheur). This is clearly distinct from single-lot retrieval (get_lot) or listing (search_lots) among the siblings, even without naming them.

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 downstream instructions: fill recommended_lot_id with the lot best matching the buyer's project, provide 2-4 short reasons grounded only in compared lot data, and never re-ask contact details in chat. It never states when to prefer this over get_lot or search_lots, so the alternative-selection guidance is implicit rather than explicit.

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