get_data_transfer_costs

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

No annotations are provided, so the description carries full burden for behavioral disclosure. It states the tool returns findings with recommendations, implying a read-only operation, but does not disclose any side effects, auth requirements, rate limits, or that it queries the AWS Cost Explorer API. The behavioral transparency is adequate but not thorough.

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 with two paragraphs and a bullet list of examples. It front-loads the purpose and then adds details. The examples are helpful but add a bit of redundancy. Overall, it is well-structured and not verbose.

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 three optional parameters and no output schema, the description provides sufficient information to use the tool: it clarifies the scope, what data is returned (findings with recommendations), and the effect of each parameter. It lacks explicit return format details, but for a query tool, this is acceptable.

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 0%, so the description must compensate. It explains start_date and end_date as ISO dates with defaults, and threshold_usd as a minimum cost filter with default $50. This provides meaningful semantics for all three parameters, though it could mention the date range's 30-day default more explicitly.

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 identifies significant data transfer cost line items from AWS Cost Explorer, listing specific types (internet egress, cross-AZ, inter-region, NAT Gateway) and that each includes a cost-reduction recommendation. This is a specific verb-resource combination that distinguishes it from sibling tools like 'audit_aws_waste' or 'benchmark_costs'.

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 example queries that imply when to use the tool (e.g., 'What are our data transfer costs?'), but it does not explicitly state when not to use it or mention alternative tools for other cost types. The guidance is implied rather than explicit.

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