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

Annotations already declare readOnlyHint, openWorldHint false, idempotentHint, and destructiveHint false, so the safety profile is covered. The description adds substantial value beyond annotations: it specifies the computation formula, the 2026-2027 scope, a direct REST fallback endpoint, documentation URL, and output field names. It does not disclose auth or rate-limit behavior, but those are likely irrelevant for a read-only calculator.

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?

The description is long and contains redundant sections that duplicate structured data: it lists inputs that the schema already describes, enumerates output fields despite an output schema existing, and includes a formula that may not be needed. While it is front-loaded with usage guidance and well-organized, much of the content does not earn its place.

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's complexity, rich schema, annotations, and output schema, the description is complete and leaves no critical gaps for an agent to invoke it correctly. It even adds extra context like REST fallback and docs. It could be slightly more focused, but it is certainly complete enough.

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 the input schema already documents each parameter fully. The description repeats the parameter names and types and provides a complete JSON argument example, but that example largely mirrors the schema's own examples. It adds little semantic detail beyond what the schema already provides, so the baseline 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?

The description clearly states the tool counts working and non-working dates for a selected Australian state or territory in 2026-2027. It distinguishes the resource (Australian state/territory) from other country siblings, but does not explicitly differentiate itself from close siblings like add_australia_working_days or check_australia_working_day beyond the verb count in its name.

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?

It provides explicit when-to-use guidance ('Use this when you need an auditable state/territory working-day count') and when-not-to-use guidance ('Do not use this when the division is unknown or the task requires a local/employer/exchange calendar'). Alternatives by name are not listed, but the context and exclusions are clear enough for an agent to decide correctly.

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