calculate_working_days

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

Discloses exclusion of Saturdays, Sundays, and all 10 Portuguese national public holidays, plus the exact return shape. Annotations already indicate safe read (readOnlyHint, idempotentHint), so description adds valuable context without contradicting.

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 sentences, front-loaded with core function, and no wasted words. Every sentence adds value: first explains what it does, second gives usage guidance.

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 low complexity (2 params, no enums, output schema exists), the description fully covers purpose, usage, behavior, and return format with no gaps.

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?

Input schema already has 100% coverage with descriptions for both parameters (including format and example). Description does not add new semantic info beyond what schema provides, so baseline score of 3 is appropriate.

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?

Description clearly states the tool counts working days between two dates, excluding weekends and all 10 Portuguese public holidays. It specifies the return shape and provides concrete use cases, distinguishing it from siblings like 'calculate_working_days_eu' which likely covers broader EU 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?

Explicitly gives three example use cases: Portuguese invoice payment deadlines, legal notice periods, and SLA response times. However, it does not explicitly mention when not to use this tool vs. the sibling 'calculate_working_days_eu', which would strengthen guidance.

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