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

Annotations already declare readOnly=true, idempotent=true and closed-world, so the safety profile is covered. The description adds genuinely useful scope context (2024 sick-leave rules included in the calculation and the reference period), but says nothing about what is returned or how the calculation handles the optional sick-leave parameter.

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?

A single front-loaded sentence with zero filler: verb, resource, scope condition, and rule version. Nothing is wasted or buried.

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?

For a 3-parameter read-only calculation with no output schema, the description covers the input-side scope adequately but never indicates what the tool produces (acquired days, remaining days, indemnity). An agent must infer the return shape from the enum text rather than the description.

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 enum description already carries the full legal ruleset (2.5 days/month, 2 days/month for non-work illness, 30-day cap, indemnity methods). The description only signals that sick leave feeds the calculation. Baseline 3 applies since the schema does the heavy lifting.

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 and resource ("Calcule les jours de congés payés acquis") with an explicit scope qualifier ("arrêts maladie compris, règles 2024"). This distinguishes it reasonably from siblings like conges_payes_indemnite and solde_tout_compte, though the distinction is implied rather than stated.

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 implies usage via the period-of-reference and arrêts-maladie scope, but never says when to call this vs. conges_payes_indemnite (which covers the indemnity side) or solde_tout_compte (the full balance). No exclusions or prerequisites are given.

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