calendar.business-days

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

With no annotations, the description carries the full burden. It discloses holiday awareness, custom weekends, and that skipped holidays are itemized. It explains the XOR relationship between addDays and end. Could mention error handling or output format, but adequate for a calculation tool.

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 well-structured sentences. First sentence sets purpose and target users, second details modes and features. No wasted words.

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?

Covers the main behaviors: three modes, custom weekends, holiday itemization. Missing output format details, but for a calculation tool this is sufficient. Could mention that addDays and end are mutually exclusive.

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 clear descriptions. The description adds value by explaining the three modes, custom weekend syntax, and that skipped holidays are itemized, which goes beyond schema parameter definitions.

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 it's a business-day calculator for 200+ countries with specific use cases (payment terms, SLA deadlines). It distinguishes from sibling 'calendar.holidays' by focusing on computation 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 explicitly details three modes of operation (start+addDays, start+end, start alone) and provides examples of custom weekends. It implies when to use (instead of guessing holidays) but doesn't explicitly state when not to use or mention alternatives.

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