get_costs_by_service

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

No annotations are provided, and the description does not disclose behavioral traits such as read-only nature, rate limits, authentication requirements, or side effects. The description only states what the tool does, not how it behaves or any constraints beyond parameter defaults.

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 concise and well-structured: a one-sentence summary, a clear list of parameters with key details, and relevant examples. It is front-loaded with the main purpose, and every sentence provides value 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?

Given the absence of output schema and annotations, the description adequately covers the parameters and provides examples, but it lacks details about the return format, pagination, or edge cases. For a tool with six parameters, this is a moderate level of completeness.

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?

With 0% schema description coverage, the description adds significant meaning by explaining each parameter: service_filter (case-insensitive substring), provider (specific provider), category (cloud or saas), start_date (ISO date, default 30 days ago), end_date (ISO date, default today), and account (named AWS account). This compensates well for the schema's lack of descriptions.

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 provides a cost breakdown by service with optional filters. It uses specific verbs ('get', 'breakdown') and resource ('costs by service'), and the examples illustrate typical use cases, distinguishing it from sibling tools like get_cost_summary or get_costs_by_team.

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 does not explicitly state when to use this tool versus alternatives. While the examples imply usage for service-level queries, no clear guidance is given on when not to use it or which sibling tools might be more appropriate for aggregate views or team breakdowns.

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