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

With no annotations, the description discloses important behavioral nuances: sorting order, and that selecting a supported category 'creates a query-free discovery receipt' with implications for provider-funded actions, while unfiltered viewing stays free and does not enter the Stage 1 demand cohort. This goes beyond a simple list operation.

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 compact at two sentences, with the first sentence directly stating the tool's function. The second sentence is dense and jargon-heavy, but it conveys necessary nuance without padding. It could be clearer but is not verbose.

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 tool is a simple list operation with three optional parameters, and the schema already documents defaults and limits. The description covers the core purpose and a critical side-effect of category filtering, making it sufficiently complete for an agent to decide whether to use it. It does not describe the return format, but that is not critical given no output schema and the simple nature.

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% for all three parameters, so the baseline is 3. The description adds significant meaning to the category parameter, explaining that supported categories trigger receipt creation while omitting category is 'unfiltered catalog watching' with different behavior. This enriches the schema's enum.

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 opens with a specific verb and resource: 'List agent-ready sites newly added to the Not Human Search index, sorted newest first.' This clearly distinguishes it from sibling tools like get_top_sites or search_agents by focusing on recent additions.

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 implies when to use this tool (for discovering newly indexed sites) and provides context about category filtering. It does not explicitly name alternatives or state when not to use it, but the purpose is clear enough to guide selection.

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