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 useful context that the output is a set of slugs consumed by xda_headlines, but says nothing about caching, rate limits, or freshness of the section list.

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 short sentences with no filler. The definition of what is returned comes first, then the routing guidance, so the most important information is front-loaded.

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 value structure needn't be explained, and a zero-param discovery tool has little else to document. The description covers purpose and downstream usage adequately, though it could note whether the slug list is stable or changes over time.

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 per the rubric this is a baseline 4. The description correctly frames the output as slugs for use elsewhere, which is the only semantic content available.

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 ('List public XDA RSS section slugs') and ties the resource to its consumer ('accepted by xda_headlines'). This distinguishes it from xda_headlines, xda_news, xda_article and xda_author without any schema inspection.

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 the agent: use xda_news for the general feed, or xda_headlines parameterised with a slug returned here. The when-to-use and which-alternative condition are both stated directly.

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