AWS MCP Server

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

With no annotations provided, the description carries full burden. It clarifies that parent_id accepts root IDs or OU IDs, adding behavioral context. However, it omits read-only nature, pagination behavior, rate limits, and error handling (e.g., what happens if parent doesn't exist).

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 resource. No redundant text, though extremely terse given the complexity of AWS Organizations hierarchies.

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?

Adequate for a list operation with complete input schema, but lacks output structure description (no output schema provided), pagination details, or AWS Organizations-specific prerequisites needed for successful invocation.

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 has 100% coverage documenting parameter formats. Description adds semantic context by mentioning 'parent (root or OU)' which aligns with parent_id, but doesn't add validation rules, optional vs required distinctions, or format examples beyond the schema.

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 'organizational units' with scope 'for a parent (root or OU)'. Distinguishes from sibling tools like list_accounts and list_roots by specifying the OU resource and parent-child relationship.

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 on when to use versus alternatives, no mention of AWS Organizations prerequisites (e.g., account must be in an organization), and no deprecation or permission requirements stated.

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