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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the agent knows this is a safe, non-mutating read. The description adds the meaningful fact that the returned set is the accepted vocabulary for wapo_headlines, but says nothing about ordering, size, or whether results are cached — acceptable given a zero-parameter static enumeration.

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?

A single front-loaded sentence with no filler; every word contributes to identifying the resource and its consumer. Nothing is buried or repeated.

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, return-value detail is unnecessary, and the description covers the one thing the agent needs: what the enumeration is and where its values belong. It could be marginally stronger by stating that these are the only accepted section identifiers.

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 tool takes zero parameters, so there is nothing for the description to disambiguate; baseline 4 applies. The description correctly avoids inventing parameters.

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 resource (Washington Post sections) and ties it explicitly to wapo_headlines as the consumer, which distinguishes it from siblings like wapo_news or wapo_article. It is a noun phrase without an explicit verb ('list/retrieve'), but the enumeration intent is unambiguous.

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 clause 'accepted by wapo_headlines' tells the agent exactly when this tool is relevant: to resolve valid section values before calling wapo_headlines. No exclusions or rate constraints are given, but the routing context is clear.

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