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

With no annotations, the description carries the disclosure burden. It does reveal a meaningful behavioral trait: titles are discarded, so the result is a bare count rather than a list of stories. However, it does not disclose return format, network dependency, or failure behavior, leaving the transparency incomplete.

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 extremely concise: two short sentences with no filler. The main action is front-loaded, and 'Titles discarded' is a useful qualifier rather than redundant text.

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 no annotations, the description should explain what the tool returns and what inputs it expects, but it leaves the role of the nine optional parameters unexplained. An agent cannot tell whether to call it with no arguments, with a feed URL, or with some other parameter. The core purpose is clear, but the invocation context is incomplete.

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 the baseline is 3 even though the description adds no parameter-level guidance. The description's mention of discarded titles loosely matches the 'feed' parameter, but it does not clarify which of the nine optional parameters, if any, are relevant to this tool.

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 a specific verb and resource: count current Hacker News front-page stories. The note 'Titles discarded' further clarifies that the output is a count, not story metadata. This is enough to distinguish it from the sibling tools, none of which share this narrow 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?

Usage is implied: use the tool when a count of current HN front-page stories is needed. 'Titles discarded' provides a weak when-not signal, but the description does not explicitly name alternatives or state when a different tool should be used instead.

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