calculate_working_days_latam

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

Annotations already indicate readOnlyHint=true and idempotentHint=true. The description adds behavioral context: inclusive dates, exclusion of weekends and national holidays including moveable Easter-based ones, and the returned fields (country, dates, working_days, holidays_excluded). It also lists supported countries. No contradictions.

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?

Three sentences, front-loaded with core functionality, followed by return fields and use cases. No redundant words or filler. Extremely efficient.

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 has an output schema (context signal), the description covers essential behavioral details: inclusive dates, supported countries, exclusion logic, and return fields. Minor omissions like max date range or error handling are acceptable for a counting function.

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% with each parameter having a description (country_code, start_date, end_date). The description does not add new meaning beyond the schema; it only mentions the return structure. Baseline 3 is appropriate as 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?

The description clearly states the tool counts working days between two dates inclusive for a Latin American country, excluding weekends and national holidays. It lists supported countries (BR, MX, CL, AR, CO) and differentiates from siblings like get_public_holidays_range_latam by focusing on counting rather than listing holidays.

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 use cases: cross-border SLA periods, invoice payment deadlines, and project timelines. It does not explicitly name alternative tools or state when not to use, but the context of siblings suggests appropriate usage. This is clear but lacks exclusion guidance.

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