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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile and open-world access are covered. The description adds that the article is public and that body paragraphs are returned, but it does not mention rate limits, invalid URL behavior, or non-Entertainment Weekly URL handling.

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, purpose first and routing second, with no redundant or filler phrasing. Every clause contributes either scope or an alternative tool.

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?

An output schema exists, so return values need not be explained, and annotations cover the read-only, open-world profile. For a single-parameter fetch tool, the description supplies enough purpose, scope, and sibling routing to call 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?

Schema coverage is 100% and the single url parameter is already documented as 'Canonical Entertainment Weekly article URL'. The description repeats 'canonical url' without adding format, example, or validation detail beyond what the schema provides.

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?

Specific verb 'Fetch' plus resource 'Entertainment Weekly article metadata and body paragraphs' makes the operation unambiguous. The second sentence names ew_headlines, ew_sections, and ew_news with their distinct scopes, so the agent can separate this single-article fetch from feed or section browsing without opening any 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 section stories to ew_headlines, section browsing to ew_sections, and the general feed to ew_news, which tells the agent when this tool is not the right choice. The condition for using ew_article itself—having a canonical article URL—follows directly from the purpose and the required schema field.

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