reporting_get_metric_set

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

With no annotations, the description carries the full burden; it does declare read-only and flags that this is an OPTIONAL Reporting API surface, which is useful context about availability/prerequisites. It does not say what happens if the Reporting API is not enabled or what an empty freshness result looks like, leaving the failure mode unexplained.

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?

Three short sentences, front-loaded with the purpose, followed by the sequencing rule and then the safety/availability notes. The trailing 'OPTIONAL Reporting API. Read-only.

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 two-parameter read tool with no output schema, the description covers what the tool returns (latest available end time per aggregation period), when to call it, and its read-only nature. Only the error/not-enabled behavior and precise response shape remain unaddressed, which is a minor gap.

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 50%: packageName is documented in the schema, and metricSet is self-documenting via its enum, so the schema does most of the work. The description adds only the framing that freshness is reported per aggregation period; it does not explain what the metric-set choices represent or how to pick one.

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 gives a specific verb and resource ('Describe a vitals metric set') and immediately clarifies the payload: data freshness, i.e. latest available end time per aggregation period. It is distinguishable from reporting_query_metric_set, though the term 'vitals metric set' is slightly narrower than the enum, which also includes memory-usage sets.

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?

It states an explicit sequencing rule: call this before reporting_query_metric_set to pick a valid time range. That is real when-to-use guidance tied to a named sibling. It does not state when to skip it (e.g. if the caller already knows a valid range), so it falls short of full when/when-not coverage.

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