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

Annotations already declare the read-only, idempotent, open-world profile, so the bar is lower. The description still adds genuine context beyond them: the data is Lifelaw-verified, comes with a legal basis article, verification date, and start date of effect, and is labelled bilingually — all useful for deciding whether to trust and how to present the result.

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?

It is front-loaded with the verb and examples, then closes with the key-discovery pointer. The opening sentence is dense — describing the return fields before the reader knows what the tool is for — but every clause carries 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?

With only two parameters, full schema coverage, and no output schema, this description is complete: it explains what is returned (value, legal basis, verification date, effect start date, labels), where the data comes from, and how to find a valid key. Nothing an agent needs to call it 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 coverage is 100%, so the key format and date semantics (default today) are already documented. The description adds value by pointing to list_params as the way to obtain valid keys, which is not in the schema and prevents guessing at lowercase dot-separated identifiers.

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 states a specific verb and resource ("Get a Korean legal reference value") and grounds it with concrete examples (statutory interest rate, minimum wage, lease renewal request period). Those examples make it clearly distinguishable from siblings like get_article or get_case, which return legal text rather than curated reference values.

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 gives explicit routing for the common blocker: "Find keys with list_params," which tells an agent where to go before invoking this tool. It does not state when to prefer this tool over get_article/get_interpretation for the same subject, but the reference-value scope is clear enough.

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