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

With no annotations, the description must carry the behavioral burden. 'Titles discarded' is a meaningful behavioral disclosure about output shape, and 'current' implies live data. But it does not mention side effects, network behavior, failure modes, or output format beyond the count.

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 highly concise and front-loaded: 'Count current Hacker News front-page stories. Titles discarded.' Each sentence earns its place. The only structural issue is that 'Titles discarded' is terse enough to be ambiguous about whether input titles are ignored or output titles are omitted.

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 tool with nine optional parameters, no annotations, and no output schema, the description is too sparse. It does not state which parameters are relevant, what the returned count represents, how failures are reported, or whether the tool should be called with zero arguments.

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?

Although the schema descriptions cover 100% of parameters, the tool description does not explain how any of the nine optional parameters relate to 'counting Hacker News front-page stories.' The only slight connection is 'Titles discarded' echoing the feed parameter, but the agent is left without guidance on which parameter, if any, should be supplied.

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 states a specific verb and resource: 'Count current Hacker News front-page stories.' This clearly distinguishes it from sibling tools like web-fetch or normalize-url. 'Titles discarded' further sharpens the purpose by clarifying that the tool returns a count, not a listing.

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 purpose implies when to use the tool: whenever the current Hacker News front-page story count is needed. However, the description gives no explicit context about when not to use it or which sibling tools would be alternatives, and the strange optional parameters make invocation ambiguous.

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