list_control_account_buckets

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

Annotations already declare readOnlyHint=true, so the safety profile is covered and the description need not restate it. The description adds useful context by naming the returned metric families, but it does not disclose default time-window behavior, pagination semantics, or how the 'latest' flag interacts with date filters. With the annotation covering safety, this is adequate but not rich.

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 sentences with zero filler. The verb and resource scope are front-loaded, and the second sentence earns its place by specifying exactly which metrics are returned. Nothing is redundant or padded.

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 list tool with full schema coverage and no output schema, the description communicates the return content clearly, which is essential since no output schema exists. Minor gaps remain — no mention of default behavior when only controlAccountId is provided, no ordering criteria — but nothing an agent needs to invoke it correctly is missing.

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% — all 9 parameters already carry type and meaning in the schema, so the description need not compensate. The description adds nothing about parameter semantics, which is acceptable at the baseline given full schema coverage.

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?

States the verb 'List' with a specific resource (bucket-level utilization data for a Control Account) and enumerates the exact returned metrics (storage, egress, ingress, API call metrics). The 'bucket-level' qualifier implicitly distinguishes it from sibling list_control_account_usages (account-level) and list_sub_account_buckets (sub-account scope) without requiring schema inspection.

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?

No guidance on when to use this tool versus its siblings. It never mentions list_control_account_usages for account-level utilization or list_sub_account_buckets for sub-account buckets, leaving the agent to infer routing purely from tool names. There is no when/when-not guidance and no named alternatives.

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