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

Annotations already cover the safety profile (readOnlyHint, openWorldHint). The description adds that this is an RSS page — implying a fixed feed rather than a searchable/filterable query — which is useful behavioral context. It doesn't disclose pagination or result-count limits, so it falls short of a 5.

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, front-loaded with the purpose and return fields, followed by the constraint and the alternative. No redundant or filler text.

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?

Return values are covered by the output schema, the single required param is documented in both schema and description, and the sibling alternative is named. Nothing an agent needs to invoke it 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%, so the schema already documents the single param; baseline would be 3. The description adds value by constraining the value to a slug sourced from nyt_sections/nyt_sections, pointing the agent to where valid inputs come from.

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), resource (one NYT section RSS page), and enumerates the returned fields (title, canonical URL, description, author, publication time, lead image). It explicitly distinguishes itself from nyt_article, so an agent can differentiate it from siblings 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?

Names the alternative (use nyt_article for one story) and states the prerequisite that `section` must be a slug from nyt_sections. Both the selection condition and the value source are explicit.

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