beta_testers__beta_tester_usages__metrics

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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint, so the safety profile is known. The description adds the important behavioral fact that output is aggregated time-series data, not individual records, which goes beyond the structured annotations. No contradictions.

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 short, information-dense sentences with the endpoint template included. Every sentence earns its place without redundancy.

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 metrics endpoint with no output schema, the description communicates the key return shape (aggregated time series) and scope (per beta tester). It does not enumerate specific returned metrics or mention required filter_apps, but schema covers parameters and the description is sufficient for selection and invocation.

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 descriptions cover all four parameters (id, limit, period, filter_apps), including enum values, so the description adds no parameter-level detail. The baseline of 3 applies because schema does the heavy lifting.

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 action 'Read' and the specific resource 'beta tester usages metrics' for a beta tester. The clarification 'aggregated time-series data, not individual records' distinguishes it from individual record tools and sibling metrics endpoints.

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 gives useful context by noting the tool returns aggregated metrics rather than individual records, which helps the agent decide when to use it. It does not explicitly name alternatives or exclusions, but the aggregated-vs-individual distinction provides clear usage guidance.

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