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

Annotations already declare readOnly/idempotent/non-destructive/closed-world, and the description adds real context beyond them: all link parameters are stored except service ones, whether declared or not, and label filtering is plan-gated. It does not describe the shape of the returned value list (order, whether counts are included), which leaves a small gap given there is no output schema.

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?

Purpose is front-loaded, then disambiguation, then behavior. Seven sentences is on the long side and the hidden_options disclaimer is somewhat defensive, but each block maps to a genuine ambiguity an agent would otherwise hit.

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, 5-parameter, no-output-schema tool this is nearly complete: it covers what the data is, where the key comes from, sibling alternatives, and the tariff caveat. Only the return structure of the paginated value list is left unstated.

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 every parameter (key, page, search, per_page, quiz_id) is already documented, including where to take `key` from. The description adds conceptual meaning about what a label is and that the tool searches and paginates by a chosen name, but no syntax or edge-case detail beyond the schema — the baseline 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?

Opens with a specific verb+resource: shows which values a link label took across this quiz's answers, and explains concretely what a label is (utm_source, student id, course number attached to the link). It explicitly distinguishes itself from three nearby things: get_quiz_report filters.extra_fields, get_quiz_variables, and the hidden_options resource.

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 routing: to find label names use filters.extra_fields of get_quiz_report (or generate_filtered_report), for declared quiz link variables use get_quiz_variables, and states that quiz://{id}/hidden_options is a different concept with no labels there. It also flags a prerequisite: label-based filtering is not available on all tariffs.

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