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

Annotations already declare readOnlyHint=true and openWorldHint=false, so safety is covered; the description goes beyond them by disclosing the ranking formula and the fact that filtering is purely optional (zero required params). It does not mention result volume, ordering stability, or pagination, but for a read-only leaderboard those are minor.

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, ranking and scope front-loaded before the filter list, with no filler. The filter enumeration runs slightly long, but each example genuinely aids slug selection.

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?

For a zero-required-param, read-only list tool with full schema coverage, no output schema, and safety annotations, the description covers what the ranking means and how to narrow it. The only meaningful gap is the lack of differentiation from get_rising, which belongs to usage guidance rather than completeness.

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%, so baseline is 3, and the description earns a bump by explaining what 'audience' and 'task' actually accept (marketers, content-creators, video-clips, inbox, research) and by decoding max_setup_level as '1 = works in a browser, 5 = requires programming', which the schema only states numerically. It omits limit and include_builder_tools, but both are self-documenting in the schema.

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 resource and scope ('This week's Viral Agent leaderboard of AI agents gaining momentum') and even the ranking inputs (star growth scaled by size, acceleration, HN attention), so the agent knows exactly what it gets. However, it never distinguishes itself from the near-synonymous sibling get_rising, which an agent could easily confuse with 'trending'.

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 lists optional filters but gives no guidance on when to reach for this tool versus get_rising or search_agents. With a sibling literally named 'get_rising' producing a similarly growth-oriented list, the absence of any disambiguation is a real selection hazard.

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