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

Annotations already cover safety (readOnly, idempotent, non-destructive, closed-world). The description adds genuine context beyond them: a cost hint ('Cheap') and output composition (students keyed by handle and short name, score only when results exist). No auth or rate-limit detail, but for a cheap read tool that is acceptable.

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: output shape first, then query examples, then a one-word cost signal. Nothing is redundant and the most important information (what you get back) is front-loaded.

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 an output schema present, return values need not be explained, and the description still summarizes them usefully. Annotations carry the safety profile and the single param is fully documented, so the only real gap is the absence of explicit sibling routing (e.g. versus get_grading_progress).

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?

Only one parameter, and schema coverage is 100% — the schema itself documents assignmentId and points to list_coursework as the source. The description adds no further parameter semantics, so the baseline 3 for full schema coverage 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+resource (per-student status on a single assignment) and enumerates the exact states returned (in progress, submitted, scored, waiting for review), plus score availability. It is distinguishable from siblings like get_grading_progress by the explicit student-status framing, though it never names an alternative to route against.

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?

Provides concrete usage context via example questions ('who hasn't finished?' or 'how did period 5 do?'), which makes the intended scenarios clear. It stops short of naming when-not-to-use or an explicit alternative tool, so it lands just under full marks.

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