query_metrics

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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is fully covered. The description adds no behavioral context beyond that, such as whether results are cached, how the range is interpreted, or how missing data is handled. It also doesn't contradict the 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 terse sentences with the core purpose front-loaded and zero filler. It is arguably over-compressed into fragments, but nothing is wasted and scanning is trivial.

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 format need not be explained, and annotations cover the safety profile. Still, the minimal text leaves usage routing and the days parameter's semantics unaddressed, making the definition only adequate for a multi-parameter analytics 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 description coverage is 0% and the schema defines no enum constraints, so the inline lists 'visitors|pageviews|sessions|events|revenue' and 'day|hour' are genuinely additive value over the schema. However, the 'days' parameter is completely unexplained — its unit, default of 30, and allowed range are left entirely undocumented, so compensation is only partial.

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 phrase 'Time series for a metric' identifies the resource and the output shape, but the verb is only implied and there is no differentiation from siblings such as get_realtime, breakdown, compare, or list_metrics. An agent can guess it queries metric data, but nothing in the text distinguishes this tool's role from the many other report tools.

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?

There is no when-to-use guidance, no prerequisites, and no mention of alternatives despite a crowded sibling list containing several overlapping reporting tools. The agent gets no help deciding between query_metrics, get_realtime, breakdown, or compare.

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