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

There are no annotations, so the description carries the burden. It mentions discarding titles and counting current stories, but it does not disclose return format, error behavior, rate limits, or whether the many optional parameters are actually used.

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, with two short sentences and no redundant detail. The core purpose is front-loaded, and the exclusion of titles is stated efficiently.

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?

Given the 9 optional parameters, no output schema, and no annotations, the description is incomplete. It does not explain the return value, whether parameters are ignored, or what edge cases may arise, so an agent has insufficient context for robust use.

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?

Though schema description coverage is 100%, the parameter descriptions are largely unrelated to counting Hacker News stories (e.g., 'Git ref name', 'IANA timezone name', 'JSON text to validate'). The tool description adds no parameter guidance, leaving an agent unable to determine which parameters matter.

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 action and resource: 'Count current Hacker News front-page stories.' The phrase 'Titles discarded' further clarifies the scope, distinguishing it from tools that fetch or return story titles.

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 description implies usage for counting only current front-page stories and explicitly notes titles are not returned, which suggests not using it when titles are needed. However, it does not name alternative tools or provide explicit when-to-use/when-not-to-use guidance.

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