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

Annotations already declare readOnlyHint=true and openWorldHint=true, so safety and network scope are covered. The description adds that the return includes 'their recent articles,' which is a behavioral detail not evident from annotations or schema, though it doesn't discuss pagination or freshness limits on those 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?

Three sentences, each carrying distinct information: the core purpose, the returned fields, and sibling routing. Front-loaded with the primary action and zero filler.

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 an output schema present, the description needn't explain return shape, and it already summarizes returned fields. Annotations cover safety; the description covers routing and scope. Nothing an agent needs to invoke correctly is missing.

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 100% and the single 'url' parameter is fully documented as 'Canonical Gizmodo author URL.' The description doesn't restate parameter meaning or add format guidance (e.g., what constitutes a canonical URL), so a baseline 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 names a specific verb+resource ('Fetch one Gizmodo author's public profile') and enumerates the fields returned (name, job title, biography, headshot, social links, recent articles). It clearly distinguishes itself from the sibling gizmodo_article, gizmodo_headlines, and gizmodo_sections tools by naming them directly.

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 explicitly routes the agent: use gizmodo_article for one story's content, gizmodo_headlines for current outlet feeds, and gizmodo_sections to browse topics. This tells the agent not just when to use this tool but also which alternatives exist and why they'd be chosen instead.

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