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

Annotations already declare readOnlyHint=true and idempotentHint=true, so this is clearly a safe read/compute operation. The description adds valuable behavioral detail beyond annotations: the exact formula, the décote coefficient behavior, coverage per regime family, and source references. It does not describe the output format/units, but the name and formula make the computed result reasonably inferable.

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 fairly long, but each part earns its place: purpose, formula, scope list, routing to the sibling, and source traceability. The core formula and routing are front-loaded; the source citations at the end are extra but not harmful. It could be slightly tighter, but it is well-structured and readable.

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 complexity (6 params, no output schema), the description provides enough context for an agent to compute the pension and route between regimes. The main gap is that it does not explicitly state whether the returned value is an annual amount, monthly amount, or in euros, though the formula and 'pension brute' wording strongly imply an annual gross pension.

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 100%, so the baseline is 3. The description adds extra semantic value by tying parameters together in the formula (traitement/salaire de référence × 75% × trimestres liquidables ÷ requis × décote), which clarifies how salaire_reference, trimestres_liquidables, and trimestres_requis interact beyond their individual schema entries.

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 the exact resource ('Pension d'un régime en ANNUITÉS') and provides the full formula, distinguishing it from the points-based sibling retraite_pension_regime. It is specific about scope: fonction publique, régimes spéciaux, IEG-CNIEG.

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 explicitly says to use retraite_pension_regime for points-based regimes (Agirc-Arrco, complémentaires, bases CNAVPL), which directly routes the agent to the correct alternative. It also enumerates the covered regimes, leaving no ambiguity about when this tool applies.

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