accounting.vat_extract

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

Goes beyond the readOnly/idempotent annotations by giving the exact formula, the default truncation behavior of rounding (DOWN/절사), the default rate, and the Decimal-string input convention. Only the full set of accepted rounding values is left implicit.

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, each carrying distinct load: purpose, computation/rounding rule, and sibling routing. The alternative is placed last, after the core semantics, which is the right ordering.

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?

An output schema exists so return values need not be explained, and the description still spells out what the two outputs are and how they are computed. Nothing an agent needs to invoke this correctly is missing.

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 0%, yet the description covers all three parameters: gross is defined as the VAT-inclusive amount, rate's default of 0.1, and rounding's default of DOWN with the meaning of truncation to integer. This compensates fully for the empty schema descriptions, with only the alternate rounding values unspecified.

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 (역산/extract) and resource (gross → supply value + VAT), and immediately disambiguates from the sibling that performs the opposite direction. An agent can select it without opening the schema.

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 names vat_add as the tool for the forward calculation (공급가액 → 공급대가), making the split between the two tools unambiguous. That is a direct when-to-use-this-vs-alternative statement.

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