AWS MCP Server

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

Zero annotations provided, yet the description carries full burden. Omits critical AWS API behaviors: whether results are paginated (they typically are), if the operation is read-only/safe, rate limiting considerations, or what fields are returned in the absence of an output schema.

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 is front-loaded and wastes no words. However, brevity arguably crosses into under-specification given the complexity of AWS EMR APIs and lack of supporting annotations or output schema.

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?

Inadequate for a 3-parameter AWS cloud API tool. Missing: output format details (since no output schema exists), pagination behavior, authentication requirements, and relationship to other EMR operations. The minimal description leaves agents guessing about critical operational aspects.

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?

Input schema has 100% description coverage, establishing a baseline of 3. The description mentions 'account/region' which loosely contextualizes the profile and region parameters, but adds no semantic clarity on cluster_states filtering or the fact that all three parameters are optional.

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 (EMR clusters) with scope (account/region). Deducting one point because it fails to distinguish from sibling tool aws_emr_describe_cluster, which retrieves detailed configuration of a specific cluster versus listing multiple clusters.

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 provided on when to use this listing tool versus the sibling aws_emr_describe_cluster for detailed views. No mention of typical use cases, prerequisites (AWS credentials), or when filtering by cluster_states is recommended.

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