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

With no annotations, the description carries the full burden of behavioral disclosure. It lists the returned fields but does not explain what 'q' means (presumably a username), how errors are handled, whether it is read-only, or any rate limits. This is a minimal snippet of behavior, not a transparent explanation.

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 short and front-loaded, but it is also redundant ('Hacker News User' and 'HN' are the same) and omits critical parameter information. Being brief is not enough if essential semantics are missing.

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?

While an output schema exists (so return values are technically defined elsewhere), the description still fails to explain the input parameter, usage scenarios, or behavior on missing users. For a simple one-parameter tool, this is inadequate context for an agent to invoke it 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?

The input schema defines a 'q' parameter with a default of '' but no description. The tool description never mentions 'q', and schema description coverage is 0%. An agent cannot determine that 'q' is the Hacker News username or how to format it, making the tool effectively unusable without external knowledge.

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 identifies the resource (Hacker News user profile) and the data it returns (karma, created, submission count), which is specific enough to distinguish from sibling tools like hnsearch or hackernews that focus on posts or search. The verb is implied ('get'/'fetch') rather than explicit, but the intent is clear.

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?

There is no guidance on when to use this tool versus alternatives like hnsearch or hackernews, nor any mention of prerequisites or typical use cases. The description simply states what it returns, leaving the agent to infer usage context.

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