AWS MCP Server

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

No annotations provided, and description fails to disclose behavioral traits: does not confirm read-only safety, does not describe pagination behavior (truncation/next tokens), does not describe output format, and does not mention AWS API rate limiting considerations.

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 with the action and contains no redundant words. However, given the lack of annotations and output schema, the extreme brevity contributes to under-specification rather than efficient communication.

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?

With no output schema, no annotations, and only a minimal description, the tool definition lacks necessary context for an AWS resource enumeration operation. Should describe pagination behavior, output structure (e.g., function names/ARNs returned), and multi-region considerations.

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%, so the schema fully documents all three parameters. The description adds no parameter-specific guidance beyond what the schema already provides, warranting the baseline score of 3.

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 clear verb (List) and resource (Lambda functions) with scope (account/region). However, it does not explicitly differentiate from sibling tools aws_lambda_get_function or aws_lambda_invoke, leaving the agent to infer the distinction.

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?

Provides no guidance on when to use this tool versus alternatives like aws_lambda_get_function or aws_lambda_invoke. No mention of pagination behavior (despite max_items parameter) or when region/profile overrides are necessary.

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