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

With no annotations, the description carries the behavioral burden. It discloses that titles are not returned, which is a meaningful behavioral trait, but it does not describe the return format, data source freshness, network dependence, or failure behavior.

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 core purpose is front-loaded, and 'Titles discarded' adds a useful behavioral clarification without bloating the 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?

The tool has nine optional parameters and no output schema, yet the description does not explain whether any parameters affect the count, which ones are relevant, or what the return value looks like. This leaves significant ambiguity for an agent deciding how to invoke the tool correctly.

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 schema already documents the nine parameters. The tool description adds no parameter-specific guidance, but because the schema is complete, the baseline of 3 applies.

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 uses a specific verb, 'Count', and a specific resource, 'current Hacker News front-page stories'. 'Titles discarded' clarifies the output is a count rather than story content, and there are no sibling tools with a similar 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?

The description implies when to use the tool: when a count of current Hacker News front-page stories is needed. However, it does not explicitly name alternatives or state when not to use it beyond the hint that titles are discarded.

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