get_documentdb_costs

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

No annotations are provided, so the description carries full burden. It discloses that the tool queries Cost Explorer and CloudWatch, analyzes compute/storage, and flags downsizing opportunities. It does not explicitly state it is read-only, but the actions described imply no side effects.

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 (three lines for purpose, two lines for parameters) and front-loaded with the main function. Every sentence adds 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 presence of an output schema, the description adequately covers the tool's functionality: analyzing costs, breaking down compute vs storage, and recommending downsizing. No additional details about return values are needed.

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?

The description adds meaning beyond the schema for both parameters: 'days' is explained as 'Number of days to analyze (default 30)' and 'account' as 'Reserved for future multi-account support.' Since schema coverage is 0%, this fully compensates and provides clear context.

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 analyzes Amazon DocumentDB costs by cluster with rightsizing recommendations, and specifies it pulls Cost Explorer spend, breaks down compute vs storage, and checks CPU utilization. This distinguishes it from generic cost tools and other sibling tools focused on different services.

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 implies usage for DocumentDB cost analysis and rightsizing, but does not explicitly state when to use this tool versus alternatives like 'get_rds_rightsizing_recommendations' or other service-specific cost tools. No prerequisites or exclusions are provided.

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