query_metrics

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

Annotations already declare readOnlyHint=true and destructiveHint=false, covering the safety profile. The description adds query syntax examples but does not disclose additional behavioral details such as rate limits, pagination, or error behavior. Given the annotations, this is adequate but not enriched.

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?

The description is concise and front-loaded: it states the purpose in the first sentence, follows with when to use it, and then gives four terse example queries. No wasted words; every line contributes to understanding.

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 a complete input schema, an output schema, and clear annotations, the description covers the essential aspects for selecting and invoking the tool. It provides enough examples to construct valid queries, while the output schema handles return value documentation. Minor gaps (e.g., no note about complex query construction) prevent a perfect score.

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?

The schema already describes all three parameters with 100% coverage, so the baseline is 3. The description adds value by providing concrete example values for the query parameter (e.g., 'avg:system.cpu.user{*}'), which clarifies the expected syntax beyond the schema's generic description.

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 clearly states the tool 'Query and visualize time series metrics' – a specific verb and resource. It also provides concrete examples for CPU, memory, host, and tag queries, which differentiates it from sibling tools like 'list_available_metrics' or 'describe_metric' that focus on metadata discovery.

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 includes an explicit 'Use this when' clause: checking system performance, resource usage, or custom metrics. This gives clear context, though it does not mention when not to use it or name alternative tools, so it stops short of a 5.

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