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 is covered. The description adds the constraints that results are 'current' and limited to 'one public section', which is useful scoping, but says nothing about pagination, result volume, or rate behavior. Moderate added value on top of annotations.

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 sentence with the resource front-loaded, the scope constraint and the parameter-provenance guidance packed in with zero filler. Every clause earns its place.

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 simple one-parameter listing tool with a rich schema, output schema, and safety annotations, the description covers purpose, scope, and where to source the parameter. Return-value detail is correctly left to the output schema. Only a brief note on result volume or recency window would fully close the gap.

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 schema already enumerates documented slug values, so the baseline would be 3. The description goes beyond that by naming the authoritative source for valid values (straitstimes_sections), which is guidance the schema itself does not provide, and adds the constraint that only one section may be requested at a time.

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 and resource ('headlines for The Straits Times') plus a scope constraint ('one public section'), so an agent can distinguish it from straitstimes_news and straitstimes_article without opening schemas. It does not explicitly name a sibling the way the highest-scoring examples do, so sibling differentiation is inferred rather than stated.

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?

Provides a clear prerequisite: the section value 'must come from straitstimes_sections', routing the agent to the companion discovery tool before calling this one. It gives context for valid use but does not state when NOT to use it or contrast it against straitstimes_news for non-headline needs.

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