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

Beyond the annotations, the description explains why readOnlyHint is false: 'Uses one read and saves the result in the user's Puley history', which discloses both a credit cost and a persistent side effect the agent would otherwise misjudge. It also warns that the 0-100 scale is relative, not a search count, preventing a serious misinterpretation of results. It stops short of noting rate limits or failure behavior.

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, front-loaded with what the tool returns before the parameter details, and every clause carries information. The 'Uses one read' sentence sits awkwardly between parameter notes and the scale caveat, slightly interrupting the flow.

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?

With no output schema, the description still explains what comes back: a time series, top regions, and top/rising related queries. Combined with the parameter value domains and the credit/history side effect, an agent has everything needed to call this correctly.

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 carries the full burden and does: terms is comma-separated and capped at five, country is a two-letter code or 'worldwide', and period is enumerated as month / 3months / year / 5years. The accepted values for all three parameters appear nowhere else in the structured 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?

The description states the specific resource and scope precisely: Google search interest for up to five terms, comparison regions, and related searches, on a 0-100 relative scale. It never names or contrasts with a nearby sibling such as keyword_research or google_results, so the agent must infer the boundary, which keeps it below a 5.

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?

Usage is only implied: the agent can work out this is for relative search-interest over time, and the 'up to five terms' limit is a useful constraint. There is no explicit when-to-use, when-not-to-use, or pointer to alternatives like keyword_research for volume data.

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