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

No annotations are provided, so the description carries the full burden. It only says 'Titles discarded,' which is vague and doesn't disclose network access, side effects, or whether the count is exact or estimated. The parameter schema mentions 'discarded after the shape check' for several fields, but the description doesn't explain the tool's overall behavior beyond counting.

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 short (one sentence) but under-specified rather than concise. It lacks essential context about the parameters and the meaning of 'Titles discarded.' The structure doesn't aid comprehension.

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?

With 9 parameters, no output schema, and no annotations, the description is grossly incomplete. It doesn't explain how the parameters influence the count, what the return value looks like, or any prerequisites. An agent would struggle to call this 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%, with each of the 9 parameters individually described (e.g., 'Git ref name; discarded after the shape check'). The description adds no additional parameter meaning, but since the schema already covers all parameters, the baseline of 3 is appropriate.

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 Hacker News front-page stories. This is clear and distinct from sibling tools like web-fetch or fetch-status. However, it doesn't explicitly differentiate from other counting tools (e.g., memory-key-count) but the target is specific.

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?

No guidance on when to use this tool versus the many siblings (web-fetch, fetch-status, search-query-len, etc.). There is no mention of context, prerequisites, or exclusions.

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