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

There are no annotations, so the description carries the full burden, but it only restates the action ('Get random year trivia'). It does not disclose that this is likely a network fetch, how randomness works, potential failure modes, or anything about the response shape. For a no-annotation tool, this is a significant gap.

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?

The description is a single concise sentence, which is appropriate for a zero-parameter tool. However, the '[COST: ]' prefix is a placeholder artifact that adds no information and slightly detracts from structure.

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 parameters and an output schema present, the core call is simple. Still, the description omits any context for distinguishing this from the many similar trivia tools in the sibling list, so an agent cannot judge when to select it.

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?

The tool has zero parameters, and schema coverage is trivially 100% with an empty properties object. No parameter documentation is needed, so the baseline of 4 for a zero-parameter tool 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?

The description says 'Get random year trivia' – a specific verb ('Get') and resource ('year trivia'). It is distinguishable from siblings like get_date_trivia and get_math_trivia by the 'year' qualifier, though the exact nature of 'year trivia' (e.g., facts about a specific year) is left implicit.

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?

No guidance is provided about when to use this tool instead of the many similar sibling tools such as get_date_trivia, get_math_trivia, or get_trivia_question. The description gives no context or exclusions, leaving the agent to guess based on names alone.

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