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

Annotations already declare readOnlyHint and openWorldHint, and the description adds substantial behavioral detail: the backend parameter behavior with exact entry counts, output contents (growth percentages, relative volume index, news articles), and the fallback logic for 'auto'. This goes well beyond the structured annotations.

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 two sentences, front-loaded with the core purpose and followed by a concise technical detail about the backend parameter. No unnecessary words; every sentence earns its place.

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 description covers the core purpose, usage context, and backend variations, which is adequate for a simple list tool with no output schema. Minor gaps remain: it does not explain how 'limit' interacts with the fixed counts of rpc/rss, nor detail the exact output structure, but these are not critical for correct invocation.

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%, covering all three parameters. The description adds meaningful semantics for the 'backend' parameter by explaining the output differences between rpc, rss, and auto, which is not fully captured in the schema. The descriptions for limit and region are sufficient in the schema, so no additional compensation is needed.

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 action ('Lists the searches surging right now in a country') and scope, and explicitly distinguishes from term-based tools by noting it works 'without a term being named' and targets 'news and real-time context'. This clearly separates it from sibling tools like get_interest_over_time or get_related_queries.

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 gives explicit when-to-use guidance: 'for questions about what is spiking without a term being named, and for news and real-time context.' It implies when not to use (when a specific term is already known) but does not name alternative tools or provide exclusions, so it falls just short of a 5.

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