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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safe-read profile is covered. The description adds modest context ('public' profile, recent articles) but there is a dedicated output schema, so listing returned fields is largely redundant, and nothing is said about pagination or freshness of 'recent articles'.

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?

Two sentences, zero waste, front-loaded with the resource and its payload before the routing hint. Nothing needs re-reading or decoding.

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 one-parameter read tool with an output schema covering the return shape and annotations covering safety, the description supplies everything needed to call it correctly. Only the lack of guidance relative to the other kotaku_* siblings keeps it short of full completeness.

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?

There is a single 'url' parameter with 100% schema description coverage ('Canonical Kotaku author URL'), so the schema carries the meaning. The description adds no syntax, format, or example for the URL beyond what the schema provides, which is the baseline-3 case.

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?

States a specific verb (Fetch) and resource (one Kotaku author's public profile), then enumerates exactly what comes back: name, biography, headshot, social links, recent articles. It also names the sibling it is not (kotaku_article), so an agent can route without opening a schema.

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?

Explicitly routes the agent away from kotaku_article with 'Use kotaku_article for one story's content', giving a clear selection condition. It does not, however, address the other plausible siblings (kotaku_headlines, kotaku_news, kotaku_sections), so guidance is partial rather than complete.

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