trends_compare

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

Annotations already declare readOnlyHint, idempotentHint, and openWorldHint. The description adds meaningful behavioral context beyond those: the 0-100 relative scale, the returned metrics (time series, mean, peak), and the explicit note that interest is relative rather than absolute. No contradiction with 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?

Two sentences with no filler. The first sentence states the action, scope, and output; the second clarifies the scale and the relative-versus-absolute limitation. Everything included 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?

Given the output schema, annotations, and simple three-parameter input, the description covers the essential invocation context: what the tool compares, what it returns, and the key interpretational caveat. No critical operational detail appears missing.

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 67%, with geo and timeframe already documented. The description adds little per-parameter meaning beyond the schema: it clarifies that keywords are compared, but 'up to 5' is already encoded in maxItems, and no additional guidance is given for keyword formatting, geo values, or timeframe syntax.

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 uses a specific verb ('Compare'), names the resource ('Google Trends'), and defines the scope ('up to 5 keywords'). It also states the output ('time series, mean and peak') and the key limitation ('relative interest only, not absolute volume'), which clearly distinguishes it from volume-oriented siblings like estimate_volumes.

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 clear context for when to use the tool: comparing up to 5 keywords on a shared scale. It explicitly excludes absolute-volume use cases, which is a useful when-not signal, though it does not name alternative tools such as estimate_volumes or trends_related.

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