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

Annotations already declare readOnlyHint and idempotentHint, so no safety disclaimer is needed. The description adds behavioral context beyond those: it returns only other listings in the same category and sorts them 'most upvoted first,' which an agent cannot infer from the schema or annotations alone.

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 sentences with no filler: the first defines the tool's behavior and output ordering, and the second supplies a practical use case. Every word earns its place, and 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?

The output schema is present, so return-value details are already specified. The description covers selection logic, ordering, and use case; the schema covers parameters; and annotations cover safety. Nothing essential is missing for an agent to invoke this tool correctly.

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 100%: both 'slug' and 'limit' have descriptive text in the input schema. The description's 'given listing' implicitly refers to slug but adds no parameter semantics beyond what the schema already provides, so the baseline score of 3 applies.

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 states a specific outcome: 'Other SaaSCity listings in the same category as a given listing, most upvoted first.' It makes clear the resource (SaaSCity listings), the selection logic (same category), and the ordering, which distinguishes it from siblings like search_listings, get_listing, and get_leaderboard.

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 phrase 'Useful for competitor research and positioning' provides a clear use case, but the description does not explicitly guide the agent on when to choose this tool over related alternatives such as search_listings or get_listing. The usage guidance is implied by the definition rather than stated as a decision rule.

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