AWS FinOps MCP Server

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

No annotations are provided, so the description carries the full burden. It discloses the tool's purpose and return type (dictionary with ASGs using old AMIs), but lacks details on behavioral traits such as required AWS permissions, potential rate limits, whether it performs read-only operations (implied by 'Find'), or error handling. The description does not contradict any annotations.

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 well-structured and front-loaded with the core purpose, followed by organized sections for arguments and returns. Each sentence earns its place by clarifying parameters and output without redundancy, making it efficient and easy to parse.

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 complexity (8 parameters, no annotations, but with an output schema indicated), the description is largely complete. It explains the tool's purpose, parameters, and return type. However, it could improve by addressing behavioral aspects like permissions or limitations, though the output schema may cover return values. It's adequate but has minor gaps in behavioral context.

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 fully. It provides detailed semantics for all 8 parameters, including their purposes (e.g., 'region_name: AWS region name', 'period: Minimum age in days for AMI to be considered old'), defaults, and optional status. This adds significant value beyond the bare schema.

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 specific action ('Find Auto Scaling Groups using AMIs older than the specified period'), identifies the target resource (Auto Scaling Groups with old AMIs), and distinguishes it from siblings like 'find_unused_amis' (which finds unused AMIs) or 'find_ec2_instances_with_old_generations' (which focuses on instance generations rather than AMI age in ASGs).

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 identifying outdated AMIs in ASGs based on age, but does not explicitly state when to use this tool versus alternatives (e.g., 'find_ec2_instances_with_old_generations' for instance types, or 'find_unused_amis' for unused AMIs). It provides context (AWS region, AMI age threshold) but lacks explicit guidance on exclusions or prerequisites.

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