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

Annotations already declare readOnlyHint=true and openWorldHint=true, so safety is covered. The description adds useful non-obvious context beyond that: results are "current" (freshness), only one section per call, and the valid-value dependency on arstechnica_sections. Return format/pagination is left to the output schema.

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 that states the resource, the scope, and the input constraint with no 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?

For a one-parameter tool with full schema coverage, an output schema, and safety annotations, the description supplies the missing pieces (call scope, freshness, input source). It is essentially complete, with only the headline-vs-news distinction left implicit.

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 even lists the documented section slugs, so the schema carries most of the load. The description adds the cross-tool constraint that values must originate from arstechnica_sections, which is meaningful information not present in the schema itself.

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 gives a specific verb+resource ("Current Ars Technica headlines") and constrains scope to "one public section." It distinguishes the tool by its headline-only, section-scoped framing, though it never explicitly contrasts itself with siblings like arstechnica_news or arstechnica_sections.

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?

It provides a concrete operational rule: the section argument "must come from arstechnica_sections," which routes the agent to the prerequisite tool. It lacks an explicit when-not clause (e.g., distinguishing from arstechnica_news), so it falls just short of full guidance.

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