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

readOnlyHint=true already covers the safety profile, so the description only needs to add context. It does: it discloses the output ordering convention (building number first, then street, district, city) via the example, and states 'Free,' which tells the agent there is no cost gate. It omits failure behavior for malformed or non-road-name input.

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?

One sentence plus one inline example; the verb and scope are front-loaded and the example is embedded rather than appended as filler. Nothing is wasted.

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 tool with no output schema, the arrow example effectively communicates the return shape and ordering, so an agent can call it confidently. The only gap is error/edge-case behavior for unsupported address types, which is minor here.

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% for the single 'address' parameter, so the description must carry the load — and it does, specifying Hangul input, road-name form, and a literal example value. It still does not say what happens with non-Hangul or non-road-name strings.

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 (convert) and a tightly scoped resource (Korean road-name address in Hangul) with both direction and output form. The concrete before/after example makes the transformation unambiguous and clearly separates it from generic siblings like romanize_korean or romanize_korean_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?

Names the intended context ('shipping labels / forms'), which tells the agent when this is the right tool. It does not name alternatives or state when-not to use it (e.g., jibun/land-lot addresses or already-romanized input), so it falls short of full routing guidance.

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