Get cost summary

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

Annotations already declare read-only, idempotent, non-destructive, and open-world behavior. The description adds the aggregation dimensions and example queries, but omits permissions, data freshness, currency, and response shape.

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 brief and front-loaded with the core behavior. The examples are short and earn their place by illustrating realistic usage.

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?

With six undocumented optional parameters and no output schema, the description does not provide enough detail for an agent to use the filters correctly. It is sufficient for a broad summary call but incomplete for parameterized cost queries.

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?

There are six optional parameters with 0% schema description coverage. The description mentions account and examples imply dates and provider, but it does not explain account/category/provider formats, date syntax, or valid granularity values.

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 gives a specific verb and resource: get total spend summarized by service, account, and region. It is clear what the tool returns, but it does not explicitly distinguish itself from siblings such as estimate_change_cost.

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 examples clearly show when to use the tool, such as asking about last month's spend or an AWS cost summary for January. There are no explicit exclusions or named alternatives, but the usage context is concrete.

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