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

No annotations exist, so the description carries the full burden of behavioral disclosure. It communicates only that top stories are returned, but does not disclose output shape, story count, ordering, freshness/pagination behavior, or whether anything else happens server-side. For a data-fetching tool with zero annotation support, this is a meaningful 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 sentence with no waste, but the leading token 'Hn Top:' largely restates the tool name, and the total content is minimal to the point of under-specification. It is concise but does not use its space to add operational detail that the name alone doesn't already convey.

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 zero-parameter tool there is no invocation complexity to document, and the description correctly identifies the data source and content. However, with no output schema and no annotations, an agent is left without information about the result format, count, or any cap/limit behavior — acceptable for a trivial fetch tool, but not complete.

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, so the schema already fully documents the invocation surface (empty properties object). Per the baseline for zero-param tools, the description does not need to explain parameters, and nothing in its text misleads about inputs.

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 clarifies the opaque acronym: 'Hn Top: Hacker News top stories' tells an agent the tool returns Hacker News's top story listing. The resource ('Hacker News top stories') is explicit and the intent (retrieve/list) is easily inferred, though no explicit verb is used and it does not differentiate from siblings beyond the fact that no other HN tools appear in the list.

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?

There is no guidance on when to use this tool versus alternatives, no mention of prerequisites, and no exclusions. Given the enormous sibling list (thousands of tools), the absence of any routing signal leaves the agent to infer use purely from the name and the one-line description.

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