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

Annotations already declare readOnly, idempotent and non-destructive, so the safety profile is covered. The description adds genuinely new behavioral context: the cost signal ('Cheap') and the promise that each row carries identifiers plus the review operation to perform, which tells the agent this is a routing/dispatch listing rather than raw data.

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 front-loaded sentences covering scope, row shape and filtering, plus a terse cost note. The clipped 'Cheap.' fragment is efficient though slightly informal; no filler otherwise.

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?

An output schema exists, so return values need not be spelled out, and the description helpfully flags the row contents. But for a 5-param tool with 20% schema coverage, the unexplained `filter` enum and pagination semantics leave a real gap before an agent can call it confidently.

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 20% across 5 params, so the description should compensate but largely does not. It gestures at 'filter by subject or assignment' (subjectSlug, assignmentId) but never explains the critical `filter` enum (all/review/handback), the limit default/max, or cursor pagination — the exact values a caller must choose.

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 ('teacher's review queue') and enumerates the three item categories it returns (free responses needing scoring, imported essays awaiting approval, assignments ready to hand back). This scope is distinctive enough to separate it from siblings like get_submission or list_coursework.

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 'as on the website inbox' framing and the item inventory imply when to reach for it, and it notes subject/assignment filtering. However, it names no alternative tools and gives no when-not guidance, so an agent must infer routing from the sibling list.

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