List idle resources

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

Annotations declare readOnlyHint=true and destructiveHint=false. The description adds context: results are sorted by monthly waste descending, protected resources are flagged but not acted on. It does not mention rate limits or auth, but for a read-only tool this is sufficient.

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 front-loads the purpose and uses bullet points and examples effectively. Slightly verbose but all information is relevant. Could trim minor redundancy but still concise for the detail provided.

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?

No output schema exists, and the description does not detail the return format or fields beyond noting sorting by monthly waste. Given the tool finds multiple resource types, a description of output structure would improve 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?

Schema description coverage is 0%, but the description explains all three parameters: resource_types (subset to scan, default all), regions (default all enabled), min_idle_days (minimum idle days). It adds examples and defaults, compensating for the lack of schema 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 explicitly states the tool scans for idle/wasted AWS resources, lists five specific resource types, and explicitly excludes others (RDS, DocumentDB, Kendra, Textract). This clearly distinguishes it from sibling tools like get_idle_rds_instances.

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 explicit alternatives for other resource types (get_idle_rds_instances, get_documentdb_costs, etc.) and suggests run_full_cost_audit for a comprehensive check. It also gives example queries, making it clear when to use this tool.

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