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

With no annotations provided, the description carries the transparency burden. It discloses that the count is 'current' and that 'titles discarded' — useful behavioral signals. Still, it does not mention output format, whether a network fetch is performed, or any side effects, leaving some behavior unstated.

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 and front-loaded. It names the action and resource in the first sentence and adds a useful behavioral qualifier in the second. There is no filler or redundant restatement of the tool name.

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 simple count tool with zero required parameters, the description is mostly sufficient: an agent can likely call it with no arguments and expect a numeric count. However, the nine optional parameters are unrelated to the stated HN-count purpose, and the absence of an output schema leaves some uncertainty about the exact return shape.

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 of the nine parameters has a description, and most explicitly note that the value is 'discarded after' some check. The main description adds no tool-specific parameter guidance and does not map any parameter to the HN count behavior.

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 and resource: 'Count current Hacker News front-page stories.' This clearly defines the tool's core purpose. 'Titles discarded' further clarifies that the output is a count, not story titles, which distinguishes the tool from content-fetching siblings.

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 the tool should be used when a count of current HN front-page stories is needed and suggests it should not be used if titles are required. However, it does not name alternative tools or explicitly state when to prefer another sibling, so the guidance remains implicit.

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