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

Annotations already declare readOnlyHint=true, idempotentHint=true, openWorldHint=false and destructiveHint=false, so the safety profile is covered. The description's one addition is 'Moderate cost', which is genuinely useful beyond the annotations, but it stops there — nothing about rate limits, result size or how the ranking is computed, and an output schema exists so return values are already handled elsewhere.

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?

Three short sentences, purpose front-loaded, then filters, then cost. No filler; the cost sentence is arguably the only one that could be trimmed, but it carries real 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?

For a read-only analytics tool with a full input schema and an output schema, the description covers purpose, filters and cost adequately. The remaining gap is positioning relative to the other insight tools, which an agent picking among ~60 siblings would benefit from.

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 every parameter (days, classId, subjectSlug, assignmentId) is already documented in the schema. The description only paraphrases the filter set, adding no format or syntax detail beyond the schema, so the baseline of 3 applies.

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 (ranks) plus the resources ranked (topics, units, CED skills, FRQ rubric rows) and the criterion (points lost on Fiveable assignments). Clear and concrete, but it never names a sibling, which matters here because get_class_insights, get_skill_insights and get_assignment_question_breakdown sit in adjacent territory.

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 conveys scope ('optional filters cover class, subject, assignment and time window') and a cost signal, implying it is used for diagnosing class-wide weakness. But there is no explicit when-to-use or when-not, and no routing to alternatives such as get_class_insights or get_skill_insights.

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