Query trend

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

Annotations already declare readOnlyHint=true, openWorldHint=true, and destructiveHint=false, so safety behavior is covered structurally. The description adds the returned metrics (clicks and impressions), which is useful content, but says nothing about default date range, granularity, or result limits.

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?

A single tight sentence with the resource and scope front-loaded and zero filler. Nothing could be removed without losing meaning.

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 low-complexity read tool with full schema coverage and clear read-only annotations, this is nearly adequate. The notable gap is that omitting the optional startDate/endDate has an unknown default behavior that is never disclosed.

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%, so all four parameters (query, siteUrl, startDate, endDate) are already documented in the schema, including the list_sites hint for siteUrl. The description adds no format or date-range semantics beyond 'for one query', so baseline 3 applies.

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 (time series of clicks and impressions) scoped to one query, which is a clear verb-equivalent and tells the agent this is a temporal breakdown rather than an aggregate. It implicitly separates itself from get_query_stats via 'Time series', but never names siblings explicitly, so it stops short of 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?

No when-to-use, when-not-to-use, or alternative routing is given. The phrase 'for one query' implies single-query scope, but an agent must infer on its own when to pick this over get_query_stats or get_traffic_trend.

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