datetime.tax_period_kr

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

Annotations already cover read-only, idempotent and closed-world behavior, so the description's job is to add domain semantics — which it does by citing the governing statute, fixing the calendar-year convention, and disclosing the exclusion of partial periods. It doesn't say what the boundary dates look like (inclusive/exclusive) or how leap years are treated, a minor residual gap.

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, no filler: the affirmative definition with its legal anchor comes first, the scope exclusions second. Dense and front-loaded, with every clause carrying information.

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?

For a one-parameter read-only tool with an output schema, the description is nearly complete: purpose, format, legal basis and exclusions are all present. What's missing is only the shape of the returned boundary values and how dated edges (e.g. exactly the last day of the year) are handled, which is minor given the output schema.

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 0% and the single as_of property has no description, so the description carries the full burden. It supplies both the expected format (YYYY-MM-DD) and the semantic role (the reference date whose period is being determined), which is enough to call the tool correctly.

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 (returns tax_year and boundary dates) and a precisely scoped resource (Korean income tax period under Income Tax Act Art. 5, Jan 1–Dec 31) keyed off the as_of date. The explicit statement that it does not cover corporate fiscal years separates it from datetime.fiscal_year and datetime.fiscal_quarter without requiring a schema comparison.

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?

Gives clear negative guidance: not for mid-year terminations caused by business start/closure, death or departure, and not for corporate fiscal years. It stops short of naming the sibling an agent should use instead (e.g. datetime.fiscal_year) for that fallback case, so routing is implied rather than explicit.

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