b2_rank_egress_leaders

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

Beyond the readOnly/idempotent annotations, the description adds meaningful behavioral context: it relies on daily usage reports, defaults to month-to-date, returns shares of total egress, scopes to the caller's key, and explicitly requires Usage Reports to be enabled. This is exactly the kind of operational detail an agent needs.

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 compact and front-loaded with the core action and resource, then delivers use cases, output semantics, scoping, and a prerequisite. Every sentence contributes useful information with no filler or 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 simple read-only ranking tool with no required parameters and no output schema, the description covers the source data, default window, result content, scope, and prerequisite. It could be slightly stronger by describing the exact response fields or ordering, but nothing essential is missing for a correct 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 description coverage is 100%, so the schema already fully documents by, days, and limit. The description mostly restates what the schema says, such as ranking by account or bucket and month-to-date defaults, and does not add substantial parameter-level meaning beyond the schema.

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 uses a specific verb-resource pairing: rank top egress leaders by account or bucket over a period. It also describes the exact use cases ('who's downloading the most', 'where is egress concentrated'), which makes it easy to distinguish from sibling reporting tools like b2_report_usage_growth.

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 provides clear context for when to use the tool through intended questions and prerequisites like needing Usage Reports enabled. It does not explicitly name an alternative or when-not-to-use condition, but the use cases are specific enough that an agent can select it appropriately among the siblings.

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