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

With no annotations, the description only reveals a read-like counting operation and mentions that some values are discarded. It does not disclose return format, error behavior, or whether network access is involved.

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 very short and front-loaded with the core action and resource. However, the final clause 'Titles discarded' is unclear and could be removed or clarified without adding bulk.

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 description omits the output shape (e.g., integer vs. JSON) and fails to explain the role of the nine optional parameters. Given the tool's minimal schema and absent output schema, this is a notable gap.

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 parameters (ref, url, city, feed, host, json, path, zone, query) have descriptions like 'discarded after the shape check' that are unrelated to counting HN stories. Although every parameter has a description, those descriptions do not explain how, if at all, they affect the tool's behavior.

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 clearly states the action ('Count') and resource ('current Hacker News front-page stories'), distinguishing it from URL/status tools among siblings. The phrase 'Titles discarded' is slightly ambiguous but does not obscure the main purpose.

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 over alternatives or what inputs are meaningful. All nine parameters are optional and described as discarded, leaving the agent to guess whether any arguments should be supplied.

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