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

Annotations mark the call non-read-only and non-idempotent; the description supplies the reason by disclosing the per-conversation quota, which is exactly the behavior an agent needs to avoid wasting calls. It also asserts the question is 'checked to have one correct answer' and that results are excluded from ranking. It does not say what happens when the quota is exhausted.

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 short sentences, front-loaded with the action before qualifiers, with no filler. The quota sentence and the sibling-exclusion sentence both earn their place, though the phrasing is slightly telegraphic.

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 tool with no output schema, the description covers the key constraints: quota, language, ranking exclusion, and question validity. It could say more about what the opened question actually returns (stem, options, an id), but the essential calling context is present.

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 both parameters are already documented in structured form, and the description only echoes the existing lang constraint ('English only; lang hi is rejected'). The attemptId-by-conversation semantics are handled entirely by the schema, so the description adds no meaning beyond it.

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 opens with a specific verb and resource ('Open one extra Quant Daily practice question') and immediately scopes it against siblings: 'These are not today's shared drill and they are not in the attempt ranking.' An agent can distinguish it from get_daily_drill without opening the 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?

It makes clear this is the extra-practice path, not the shared daily drill, and states a concrete usage budget ('2 practice questions today, the anonymous allowance'). It stops short of explicitly naming get_daily_drill as the alternative for the shared drill, leaving that routing to be inferred from the sibling's name.

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