AWS FinOps MCP Server

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It states what the tool does but lacks details on permissions required, whether it's read-only or destructive, rate limits, output format, or error handling. For a tool with 7 parameters and AWS authentication inputs, this is a significant gap.

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, efficient sentence that directly states the tool's purpose without unnecessary words. It's appropriately sized and front-loaded, making it easy to understand at a glance.

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's complexity (7 parameters, AWS authentication, no annotations) and the presence of an output schema, the description is insufficient. It doesn't address authentication requirements, what 'unused' means operationally, or how results are returned. The output schema existence helps, but the description should provide more context for proper tool selection and invocation.

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 mentions 'specified period' which maps to the 'period' parameter, but with 0% schema description coverage and 7 total parameters (including authentication fields like profile_name, role_arn, access_key), it fails to add meaningful context beyond what's implied. The schema titles provide basic labels, but the description doesn't explain parameter purposes or relationships.

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') and resource ('CloudFront distributions') with a precise condition ('with no requests in the specified period'). It distinguishes from siblings like 'find_unused_amis' or 'find_unused_s3_buckets' by specifying the resource type and the 'no requests' criterion.

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 guidance is provided on when to use this tool versus alternatives. While the purpose is clear, there's no mention of prerequisites, typical use cases, or how it differs from other cost-optimization tools in the sibling list. The agent must infer usage from the description alone.

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