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

Annotations already declare readOnlyHint=true and openWorldHint=false, and the description adds genuinely useful behavior beyond them: it validates the input, performs no execution, incurs no charge, returns estimated_points and max_points, and states the result is only valid for 5 minutes. These are exactly the operational traits an agent needs and are not derivable from the annotations.

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?

Front-loaded with the core purpose, then layered with the constraints (no execution, no billing, 5-minute validity) in short, non-redundant clauses, ending with a compact [무료] tag. 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?

With no output schema, the description compensates by naming the return values (estimated_points, max_points) and the validity window, and it addresses the nested input object by stating validation against the skill's input_schema. An agent has everything needed to call this correctly and interpret the result.

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 skill_id (from search_skills), version, and the input object are already documented in the schema. The description only restates that the input is validated, adding no syntax or format detail beyond the structured fields; baseline 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?

States a specific verb and resource – 조회ing the estimated cost for a skill run – and immediately scopes it as a pre-execution preview. It is clearly distinguishable from run_skill (which presumably executes and charges) because it explicitly says it does not execute and does not bill.

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?

The opening phrase '실행 전 예상 금액 조회' establishes when to use it, and the return of estimated/max points gives the purpose of the call. It does not explicitly name run_skill as the alternative to reach for when an actual execution is wanted, so the routing is implied rather than spelled out.

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