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

With no annotations, the description carries the burden of behavioral disclosure. It states that the count is based on current front-page stories and that titles are not returned, but it does not mention network dependency, failure modes, or response shape.

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 two short sentences, front-loads the primary action, and every phrase earns its place. It is minimal without being cryptic.

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 no-required-parameter tool, the description adequately conveys that a bare call produces a count and that titles are omitted. However, the presence of many unrelated optional parameters and the absence of an output schema leave some ambiguity about response format and whether any parameter affects the result.

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?

All nine parameters already have schema descriptions, so the tool description does not need to restate them. The description adds no parameter-specific guidance, but the schema's optional flags and 'discarded' notes largely cover the semantics.

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 names a specific action ('Count') and a specific resource ('current Hacker News front-page stories'), making the tool's purpose immediately clear. It is distinct from sibling tools like web-fetch or normalize-url.

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 description gives clear context: this is for counting the current HN front page, and the 'Titles discarded' clause explicitly signals that title retrieval is out of scope. It does not name alternative sibling tools, so it stops short of full routing guidance.

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