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

Annotations declare readOnlyHint=true and openWorldHint=false, so the safety profile is already covered. The description adds useful behavioral context: it returns an *estimate* (not an authoritative grade) along with a source and page URL, which sets expectations about accuracy. It does not, however, explain rounding rules or edge cases in the relative-evaluation model.

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?

The description is compact and front-loads the core purpose before the reference URL and return note. The external URL and Korean reference line are slightly noisy, but nothing is egregiously wasteful.

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 must carry return-value meaning, and it partially does ('Returns an estimate with the source and page URL'). For a 4-parameter tool with two undocumented required params, though, it is not fully complete: an agent lacks guidance on the rank/students semantics and on what the returned estimate's scale looks like.

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 only 50%: ties and system are documented in the schema, but rank and students have no description anywhere. The description mentions the 5-/9-grade system (mapping to the system param) but adds nothing about what rank or students mean, leaving the two required parameters semantically bare.

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+resource: converting Korean high-school class rank (내신) into a 5- or 9-grade class rank. This clearly differentiates it from siblings like suneung_score (CSAT) and gpa_converter. However it does not explicitly name those siblings to sharpen the distinction.

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?

There is no explicit statement of when to use this tool versus alternatives such as gpa_converter or suneung_score. The only routing signal is the parenthetical '(5- or 9-grade system)', which implies the domain but leaves the agent to infer when this conversion applies. No prerequisites or exclusions are given.

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