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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is fully covered. The description adds that the calculation covers both employee and employer contributions, which is useful context, but discloses nothing about rate assumptions or the employer-only nature of accident_rate_pct beyond what the schema says.

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?

Two compact sentences, with the core purpose front-loaded and the return fields listed tersely. No filler or redundant restatement of the title.

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?

An output schema exists and the parameters are fully documented, so the description need not explain returns (it does anyway). Annotations cover the safety profile. The only real gap is the absence of any when-to-use framing against the many sibling payroll calculators.

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 both parameters (gross_monthly_xof, accident_rate_pct) are already documented in the schema with ranges and defaults. The description adds no syntax or format detail beyond that, so baseline 3 applies.

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 (Calculate) and a precise resource (Senegalese social contributions, CSS/IPRES) scoped to both employee and employer. This clearly distinguishes it from country/domain siblings like calculate_senegalese_income_tax or calculate_moroccan_cnss, though it never names an alternative explicitly.

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?

There is no statement of when to use this tool versus alternatives, nor any prerequisites (e.g., that gross_monthly_xof is required). The only guidance is a discovery pointer to list_bundles for related calculators, which does not help the agent decide between this and other payroll tools.

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