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, external read operation. The description adds that only one category feed is fetched, but doesn't mention return format, rate limits, or authentication needs; with annotations covering safety, this is adequate.

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?

The description is a single, efficient sentence that front-loads the action and resource, then immediately explains the required parameter source. No words are wasted.

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?

Given the tool's simplicity (one required parameter, no complex nested objects) and the presence of an output schema, the description provides all necessary context: what it does and where to get the parameter value. Nothing critical 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 description coverage is 0%, so the description must compensate. It explains that the 'section' parameter expects a slug obtained from dailykos_sections, which adds crucial meaning beyond the bare string type in the schema. This is strong, though it could specify the slug's format more precisely.

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 uses a specific verb ('Fetch') and resource ('headlines from one Daily Kos category feed'), distinguishing it from siblings like dailykos_news and dailykos_article by explicitly scoping to a category feed. An agent can immediately identify its function.

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 description instructs to 'provide a slug returned by dailykos_sections,' which clearly implies that dailykos_sections must be called first and that the section parameter comes from there. However, it does not explicitly state when to use this tool versus alternatives like dailykos_news, leaving a minor gap.

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