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

With no annotations, the description carries the full burden of explaining side effects. It mentions that titles are discarded but does not disclose network access, caching, rate limits, or whether the many accepted parameters are actually ignored.

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 short and starts with the main action, but the second sentence ('Titles discarded.') is cryptic and could have been clarified with a phrase like 'returns only the count.' It is concise but not optimally clear.

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?

The tool appears simple, but the mismatch between the purpose and the nine unrelated optional parameters creates real ambiguity. The description does not state whether to pass any parameters, what the output format is, or why the unrelated fields are accepted.

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 schema provides descriptions for all nine parameters, but the tool description connects none of them to the count behavior. Several descriptions say parameters are 'discarded' or are unrelated concepts (Git ref, weather hint, timezone), leaving an agent unable to determine which, if any, affect the result.

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 uses a clear verb ('Count') and a specific object ('current Hacker News front-page stories'), and adds that titles are not returned. It does not fully explain the 'Titles discarded' phrase, but the core purpose is easy to infer.

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 text implies the tool is for getting a count of front-page stories, but it gives no explicit guidance about when to choose this tool over siblings like web-fetch or fetch-status. No conditions, alternatives, or context are provided.

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