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

Annotations only declare readOnlyHint=true, so the safety profile is covered. The description adds the shape of the returned data (human counts by country, agent counts by model), which is useful given there is no output schema, but says nothing about errors or behavior when the question is not yet closed.

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 compact sentence that front-loads the keying parameter and packs in the breakdown of results. Dense but no wasted words; the parenthetical format note is slightly cryptic but functional.

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 and only a readOnly annotation, the description should carry more of the load for return shape and edge cases. It gives the aggregation dimensions but not enough detail for an agent to predict the payload or handle a date on which the question was not closed.

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 100%, so both 'date' (YYYY-MM-DD, before today UTC) and 'locale' (enumerated UI languages) are already documented in the schema. The description merely repeats the date format and ignores the locale parameter entirely, adding no meaning beyond the schema.

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 resource (results of a closed question) and the dimension it is keyed on (date, with format). It also previews how results are broken down (humans by country, AI agents by model). It does not explicitly differentiate itself from close siblings like get_yesterday, so it stops 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?

The phrase 'closed question' plus the schema restriction 'date before today (UTC)' implies this is for past/completed questions rather than the active one, which nudges the agent away from get_today_question. However there is no explicit when-to-use statement, no named alternative, and no exclusion for which dates are invalid.

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