AWS MCP Server

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

With no annotations provided, the description carries full behavioral disclosure burden. While 'List' implies read-only, it fails to disclose: return format (names only vs ARNs/objects), pagination behavior (critical for AWS list operations), required IAM permissions, or that results respect the profile/region parameters.

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, front-loaded with action and target. Efficient but arguably undersized given the lack of output schema and annotations requiring compensatory description.

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?

Minimal description fails to compensate for missing output schema (doesn't describe what data structure is returned) and missing annotations (doesn't confirm read-only safety or pagination). For a tool wrapping AWS API discovery, should mention pagination or result limits.

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 100%, establishing baseline 3. Description mentions 'account/region' implicitly referencing the profile/region parameters but adds no semantic context about the engine_type enum filter or the fact that all parameters are optional enabling simple discovery use cases.

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?

Clear verb (List) and resource (OpenSearch domain names) with scope (account/region). Distinguishes from sibling 'describe_domain' by focusing on 'names' vs detailed configuration. However, omits mention of the engine_type filtering capability present in the schema.

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 explicit when-to-use guidance or prerequisites mentioned. Despite having all-optional parameters, it doesn't state that calling without arguments lists all domains in the default region/profile. No comparison to sibling aws_opensearch_describe_domain.

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