trending_now

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

With no annotations, the description carries the full burden, and it does disclose non-obvious behavior: the ~24h recency window, that traffic numbers are approximate, and that filtering still fetches and caches the full feed. It omits auth/permission needs, rate limits, and error behavior, so it is strong but not complete.

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?

Three dense sentences that front-load the what and recency window, then the filter semantics, then the caching caveat. No filler, though the trailing cache note could be tightened.

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?

An output schema exists, so return-value explanation is unnecessary, and the description covers purpose, filter semantics, and caching. But with zero schema coverage, no annotations, and a trivial 'Geo'/'Max Articles' schema, the agent still lacks the geo value format and the meaning of max_articles — real gaps for a 3-parameter tool.

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 0%, so the description must compensate. It explains topic_filter precisely ('title or headlines contain every word given', with an example) and gestures at geo ('country or US state'), but never states the expected geo format (code vs. name) and says nothing about max_articles. Two of three parameters get meaningful help; the third is left entirely to inference.

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 verb and resource: 'Real-time trending searches (last ~24h) for a country or US state', plus what accompanies each trend (approximate traffic, linked headlines). That is far more specific than a name restatement. It does not, however, differentiate itself from siblings such as news_coverage, related_queries, or interest_by_region, which an agent must still disambiguate on its own.

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?

'Good for newsjacking' implies a usage context but names no alternative tool and gives no when-not condition. An agent can infer this is the real-time snapshot tool, but nothing explicitly routes it away from interest_over_time or news_coverage.

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