AWS MCP Server

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

Annotations provide critical hints: destructiveHint=true (confirms deletion), idempotentHint=true (safe to retry), readOnlyHint=false (write operation), and openWorldHint=true (external effects). The description adds minimal context beyond this, stating the target but not elaborating on consequences (e.g., network disruption, irreversible action) or AWS-specific behaviors like eventual consistency.

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 is a single, direct sentence with zero wasted words. It front-loads the core action ('Delete a subnet') and efficiently specifies the required inputs (subnet ID and region), making it easy to parse quickly.

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?

For a destructive tool with no output schema, the description is minimally adequate but lacks depth. Annotations cover safety and idempotency, but the description doesn't address critical context like error conditions (e.g., dependency failures), return values, or integration with sibling tools (e.g., use 'list-subnets' first).

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 50%, with 'region' and 'SubnetId' documented but 'DryRun' lacking description in the schema. The description mentions 'subnet ID' and 'region', aligning with schema parameters but not adding meaningful details like format examples (e.g., subnet-abc123) or explaining 'DryRun' functionality for permission checks.

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 states the action ('Delete') and resource ('a subnet by subnet ID in the given region'), making the purpose unambiguous. However, it doesn't explicitly differentiate from sibling tools like 'delete-vpc' or 'delete-route-table', which also delete AWS resources but target different entities.

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 provides no guidance on when to use this tool versus alternatives. It doesn't mention prerequisites (e.g., subnet must be empty), exclusions (e.g., cannot delete default subnets), or related tools like 'list-subnets' to identify targets or 'create-subnet' for creation.

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