AWS MCP Server

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

With no annotations provided, the description must carry the full burden. It successfully identifies the mutating nature of the operation and the readonly constraint, but omits critical details about batch atomicity, return values (e.g., change IDs), failure modes, and side effects.

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 consists of two efficient sentences with zero waste. The primary purpose is front-loaded in the first sentence, while the second sentence provides essential operational constraints without redundancy.

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?

While the input schema is rich with examples, the description provides minimal context for a complex mutation tool. Lacking annotations and output schema, it should disclose more about transaction behavior, validation rules, and the complex nested structure of resource record changes.

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 coverage is 100% and includes detailed descriptions plus a comprehensive JSON example for the 'changes' parameter. The description adds no parameter-specific semantics beyond the schema, warranting the baseline score for high-coverage schemas.

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 specifies the actions (create, update, delete) and target resource (DNS records in Route53 hosted zone). However, it does not explicitly differentiate from sibling read operations like aws_route53_list_resource_record_sets.

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?

The description notes the tool is 'Blocked in --readonly mode', indicating an execution environment constraint, but provides no guidance on when to select this tool versus read-only alternatives or prerequisites such as obtaining the hosted_zone_id.

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