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

With no annotations at all, the description carries the full burden, and it does disclose two useful traits: this is a paid call at $0.02/call and it returns titles, scores, comment counts, and author. It says nothing about rate limits, pagination, result caps beyond maxItems, or whether search hits the full text vs titles only, which matters for an unannotated tool.

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 text is front-loaded with purpose in the first sentence, then cost, then params, then an example — a sensible order with almost no filler. The dense dash-and-semicolon param listing is compact but slightly harder to scan than a plain sentence per parameter.

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 single wrapper parameter, no output schema, and no annotations, the description supplies what an agent needs to call it: what it fetches, the mode enum, the search query, the item cap, the returned field set, and the cost. The remaining gaps — maxItems default/maximum and whether results are paginated — are modest but real.

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 coverage is 0% and the top-level schema only exposes an untyped 'params' object, so the description is doing real work: it names mode with the exact enum values (search|top|new|best), defines q as the query used when mode=search, and lists maxItems as an integer. It stops short of giving default values or bounds for maxItems, and never states types for q.

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 names a specific resource (Hacker News front page) and the concrete operations involved (top/new/best stories plus full-text story search), and it lists the fields returned. Nothing in the sibling list covers the same domain, so the agent can tell at a glance this is the tech-news tool rather than one of the serp/papers tools.

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?

Usage is only implied through the mode list, which maps 'search' to the q parameter via '(mode=search)' and the worked example. There is no explicit statement of when to pick this over serp for general web queries, nor guidance on which mode to choose when the goal is just 'latest news'.

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