hmc_aggregated_metrics

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

Annotations only declare readOnlyHint. The description goes beyond by explaining the fetch mode returns the most recent document or an empty object when no metrics are available, and notes the prerequisite about PCM preferences. No contradiction with 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?

The description is well-structured and front-loaded with the main action. It is concise, using line breaks to separate key details, and every sentence adds value—mode behavior, parameter definitions, and a prerequisite. No wasted words.

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?

The tool has an output schema, so return values are covered there. The description effectively conveys the tool's purpose, required parameters, mode semantics, fallback behavior, and a prerequisite. The only minor gap is the undocumented optional parameters, but overall it's a comprehensive description for moderate complexity.

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%, so the description must compensate. It explains 'category', 'resource_name_or_uuid', 'start_ts', and 'mode' with examples and semantics. However, it does not explain 'end_ts' or 'no_of_samples', leaving two parameters without any descriptive help, which is a clear gap.

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 lists or downloads aggregated PCM metrics JSON documents. It provides concrete examples of resource types and distinguishes 'aggregated' as the long-term rollup for trend analysis, setting it apart from sibling metrics 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?

The description explicitly explains the two modes (links and fetch) and which one is the default, along with the prerequisite that aggregation must be enabled. It doesn't explicitly mention alternative tools for non-aggregated metrics, but the trend-analysis context implies when this tool is appropriate.

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