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

Annotations already declare readOnlyHint=true, so the safety profile is covered. The description adds real value by disclosing that this is a convenience wrapper over POST /api/v2/query with dimensions=[interval], which tells an agent the underlying semantics. It says nothing about result length, pagination, or rate limits on the query endpoint.

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 compact sentences with the purpose front-loaded and no filler. The second sentence adds the implementation mapping rather than padding, so every clause 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?

For a read-only query tool with 100% schema coverage, the parameters are adequately covered. However, there is no output schema, and the description does not describe the shape of the returned timeseries (timestamp buckets with metric values), leaving an agent to guess at the response format.

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%, with documented enums for interval, metrics, and date_range formats, so the schema carries the parameter burden. The description restates the interval grouping but adds no syntax, default, or format detail beyond what the schema already provides. Baseline 3 is correct.

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 (metrics) and scope (over time, grouped by a time interval), which is genuinely distinct from plausible_aggregate and plausible_breakdown. It also reveals the underlying API call, POST /api/v2/query with dimensions=[interval]. It stops short of naming siblings directly, so an agent must infer the boundary itself.

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 or when-not-to-use guidance, and no mention of the sibling tools an agent must choose between. The only signal is the implicit 'grouped by a time interval' framing, which does not say when plausible_timeseries is preferable to plausible_breakdown with a time dimension.

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