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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It reveals one behavior ('Titles discarded') and implies a read-only count, but it does not state whether live data is fetched, whether a feed URL is required, what happens on failure, or whether any inputs are ignored.

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 with the action front-loaded. 'Titles discarded' adds a behavioral detail without wasted words, though the brevity omits important usage and parameter context.

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 tool has 9 optional parameters, no output schema, and no annotations, yet the description does not specify which parameter to provide, what the return value looks like, or when to use the tool. An agent cannot confidently invoke it correctly based solely on this definition.

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. Each parameter has a meaningful description, and 'feed' even mentions 'titles discarded,' which echoes the tool description. However, the tool description itself does not explain which parameter is relevant to the HN count or how the nine optional parameters relate to the tool's purpose.

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 ('Count') and resource ('current Hacker News front-page stories'), so an agent can tell what the tool does. However, it does not explicitly distinguish this from sibling tools like web-fetch or fetch-status, and 'Titles discarded' is cryptic without additional context.

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 such as web-fetch, fetch-status, or browser-url-ok. No exclusions, prerequisites, or alternative tool names are mentioned, leaving the agent to infer usage from the tool name alone.

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