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

Annotations already declare readOnlyHint, idempotentHint, and non-destructive behavior, so the description does not need to restate those. It adds useful behavioral context about default semester selection and SAINT session requirements, which goes beyond the structured 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?

Two concise, front-loaded sentences: the first states the tool's purpose, the second covers parameter defaults and authentication requirements. Every clause adds value and there is no filler.

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 simple read-only getter with three fully documented optional parameters, the description is largely complete: it covers scope, defaults, and auth. It does not describe the exact return shape, but with no output schema and a familiar attendance-info resource, this is a minor gap.

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 baseline is 3. The description adds meaningful extra semantics by explaining that omitted year/semester fall back to the current u-SAINT term and that a SAINT login session is required. The phrase 'mcp_session_id 필요' is slightly ambiguous against the schema's optional flag, but it likely refers to needing an active session rather than mandating the parameter.

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 ('조회합니다' / retrieves), a precise resource ('u-SAINT 채플 출석 정보'), and a clear scope ('인증된 학생'). This is distinctive enough to separate it from sibling tools like get_my_schedule or get_my_grades without requiring schema inspection.

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 description gives practical usage context: year and semester are optional and default to the current u-SAINT semester, and an mcp_session_id / SAINT login is needed. It does not explicitly name alternatives, but the context is clear and there are no confusing exclusions.

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