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

Annotations already declare readOnly/idempotent/non-destructive, so the safety profile is covered; the description goes beyond that by disclosing that results include in-progress state ('written answers still to mark') and proctoring metadata ('how often they left the page'), plus the cost caveat 'Free'. It stops short of mentioning authorization scope or whether results exist only after the assessment has been started.

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?

A single front-loaded sentence that lists the returned fields with no filler; 'Free' is tacked on last and earns its place as a cost signal. Nothing in it is redundant with the title or annotations.

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 no output schema, the burden of describing the return payload falls on the description, and it does so concretely (status, score, per-answer expected comparison, ungraded written answers, minutes, page-leave count). What's missing is the single input parameter's meaning and any note on scope or empty-result behavior for applicants with no assessment.

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 0% for the single required parameter applicant_id, so the description must carry that meaning — but it never mentions the parameter at all. Only the possessive 'An applicant's tests' hints that the call is keyed by an applicant, and it doesn't clarify that the id is the hiring applicant record's integer id rather than a job or assessment id.

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?

The description names a specific resource (an applicant's assessment results) and enumerates exactly what the response contains — status, score, answers vs expected, ungraded written answers, time taken, page-leave frequency. It never states the verb explicitly (it's a noun phrase) and doesn't distinguish itself from hiring_list_assessments or hiring_get_applicant, so it falls short of a 5.

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?

There is no statement of when to use this versus hiring_list_assessments, hiring_mark_assessment (which apparently consumes the 'written answers still to mark'), or hiring_get_applicant. The only guidance-adjacent token is 'Free', which signals no credit cost but says nothing about selection between siblings.

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