Grade overview

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

Annotations already declare readOnly/idempotent/non-destructive, and the description adds real context: the default fallback to the current placement and the fact that it returns historical years. It doesn't discuss response size, ordering, or pagination for a potentially large whole-year payload, which is the main remaining gap.

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 tight sentences: payload first, default/override second, routing to alternatives last. No redundant restatement of the tool name and 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?

No output schema, but the description compensates by listing exactly what the result contains (subjects, per-period results, report grades, weights, remarks). Combined with the routing guidance and the documented default, an agent has everything needed to call it correctly.

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, but the description adds meaning the schema lacks: the default-current-placement behavior and the concrete '2025/2026' format for schooljaar. leerlingId's conditional requirement is only in the schema, not repeated in prose, keeping it just short of a 5.

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 concrete verb+resource (full grade overview per school year) and enumerates the payload: every subject, results per period, report grades, weights, remarks. It explicitly names sibling tools (subject_grades, grades_latest) and the scope each covers, so an agent can differentiate without opening schemas.

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?

Gives explicit when-to-use ('whole-year report view or earlier years') and when-to-use-else ('subject_grades for one subject, grades_latest for recent results'). The schooljaar parameter's alternate-year behavior is also framed as a usage cue.

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