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

Annotations cover the safety profile (readOnly, non-destructive, not idempotent), but the description adds substantial behavioral context annotations cannot: the exact output shape, that the answer/explanation are deliberately withheld, idempotency implications ('up to 8', optional topic), and a multi-rule usage contract (study guide authority, no PII, disclaimer, version ambiguity). This far exceeds the bar set by simple read-only hints.

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?

Front-loaded purpose is strong, but the six numbered rules make the description long and partly repetitive (rules 1, 2, and 5 all restate 'only use vetted leak questions'). Content is valuable but a more compact phrasing would retain all guidance. Appropriate size for a tool with compliance constraints, but not tight.

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, so the description must carry return-value info — and it does (question_ref, lettered options, withheld answer/explanation). It also covers the critical flow with check_answer, disclaimer obligations, and version ambiguity. Complete for what an agent needs to call and use this tool 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 baseline is 3. The description adds cross-parameter meaning beyond the schema: the 'chosen language' ties lang to list_tests languages, 'optionally for one topic' clarifies topic is a filter, and the 1-8 bound echoes count's maximum. But it doesn't explain the country/lang relationship further. Marginal uplift over the schema alone.

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 + scope ('Get up to 8 free multiple-choice practice questions for a country's citizenship test') and clarifies what comes back (question_ref, lettered options) and what does NOT come back (answer, explanation). Distinguishable from check_answer, list_tests, get_topic_summary without opening any schema.

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?

Explicitly names the next step ('after the person answers, call check_answer with the question_ref and their letter') and states when/how not to use it ('do not guess or hint the answer', 'never invent quiz questions'). This is when-to-use and when-not-to-use guidance with the alternative named.

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