AWS MCP Server

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

With no annotations provided, the description carries the full burden. It successfully adds workflow context (navigating OU trees) but omits other behavioral traits: it doesn't indicate this is read-only/safe, doesn't mention that AWS currently limits organizations to one root, and provides no hints about the return structure since no output schema exists.

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?

Extremely efficient at 12 words. Front-loaded with the action, zero redundancy, and the parenthetical clause earns its place by providing crucial workflow context without clutter.

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?

Given no output schema, the description should ideally characterize the return value (Root ID) needed for subsequent `list_organizational_units` calls. However, for a simple list operation with 100% parameter coverage and clear AWS terminology, the description is minimally adequate.

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% for the 2 parameters (profile, region), establishing a baseline of 3. The description adds no parameter-specific guidance beyond what's in the schema, but doesn't need to given the high schema coverage.

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 provides a specific verb ('List') and resource ('root(s) of the AWS Organization'), and the parenthetical '(needed to navigate the OU tree)' effectively distinguishes this from siblings like `aws_organizations_describe_organization` or `aws_organizations_list_accounts` by clarifying its role as the hierarchy entry point.

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 implies usage context ('needed to navigate the OU tree') suggesting it's a prerequisite for OU traversal, but lacks explicit guidance on when to use this versus siblings like `aws_organizations_list_organizational_units`, or whether this is always the first step in OU discovery.

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