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

Annotations already declare readOnlyHint and openWorldHint, so the safety profile is covered. The description adds meaningful context the annotations don't: the target is 'public' editorial content (no auth implied) and results are 'current' (live data), plus the article-card row shape. Pagination/rate-limit behavior is still unstated.

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 tight sentences with zero filler, and the primary action is front-loaded before the alternative-tool guidance. Every clause carries routing or scope information.

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 a single 100%-documented parameter, an output schema, and read-only annotations, the description supplies everything missing: what is returned (article-card rows), where the parameter value comes from, and which sibling handles the adjacent tasks.

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 description already tells the agent the value is a Forbes navigation path from /forbes/categories. The description's 'one public editorial section path' mostly restates that, adding only the single-value constraint. Baseline 3 is appropriate when the schema does the heavy lifting.

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?

Specific verb ('Fetch') plus resource ('Forbes article-card rows') plus scope ('from one public editorial section path'). It also names the siblings it is not (forbes_categories for path discovery, forbes_article for a single story), so an agent can distinguish it without opening any schema.

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 forbes_categories to get the section path, use forbes_article for full story content. The condition that selects this tool (wanting headline card rows for a section) is clear by contrast, though there is no explicit 'do not use when' statement.

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