aws_cost_summary

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

No annotations are available, so the description must carry the full burden. It does not disclose behavioral traits such as whether it queries the Cost Explorer API, the time period behavior, or idempotency. The description is vague and lacks detail beyond the basic purpose.

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 a single concise sentence that states the core purpose. It is front-loaded and free of verbosity. However, it could be slightly expanded to include essential context without becoming lengthy.

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 tool has two optional parameters and no output schema, the description is incomplete. It does not explain the output format, the meaning of the summary, or any caveats about data freshness or API costs. The context signals indicate a low complexity but the description fails to provide a complete picture.

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 50%, meaning one parameter ('days') has a description. The tool description does not mention any parameters or add meaning beyond the schema. The 'granularity' parameter's enum values are clear from the schema, but the description provides no guidance on usage or interpretation.

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 'Get AWS cost summary' clearly states the action (get) and resource (AWS cost summary). It is distinct from sibling tools like aws_resource_inventory, which focus on inventory rather than cost. However, it lacks specificity about what kind of summary (e.g., aggregate, per service).

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 usage guidelines are provided. The description does not indicate when to use this tool over alternatives, or any prerequisites or context for retrieval.

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