AWS MCP Server

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

No annotations provided, so description carries full burden, yet omits return value structure, pagination behavior (despite max_results parameter), read-only safety characteristics, and credential requirements. Does not explain what happens if region/profile are omitted.

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?

Single sentence with zero redundancy, appropriately front-loaded. However, brevity crosses into under-specification given lack of annotations and output schema, preventing a 5.

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?

Fails to compensate for missing output schema by describing return format (cluster ARNs? names? statuses?). With no annotations and 3 optional parameters, description should explain behavior, pagination, and credential resolution, but provides only high-level purpose.

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 has 100% description coverage, establishing baseline 3. Description adds minimal semantic value beyond schema (only 'account/region' vaguely maps to profile/region params). Does not explain that max_results is optional or parameter interactions.

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?

States specific verb (List) and resource (EKS clusters) with scope (account/region). However, does not explicitly distinguish from sibling aws_eks_describe_cluster or clarify that it returns identifiers/names rather than full cluster details.

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 when-to-use guidance, no mention of prerequisites (AWS credentials/profiles), and no distinction from alternative discovery tools like aws_eks_describe_cluster which requires a cluster name obtained from this list.

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