AWS MCP Server

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

Annotations cover key behavioral traits: readOnlyHint=false (mutation), openWorldHint=true (flexible inputs), idempotentHint=true (safe retries), destructiveHint=false (non-destructive). The description adds context by specifying the target resources (subnet/gateway), which isn't in annotations. However, it doesn't disclose additional behaviors like permissions needed, error conditions, or effects on network routing, leaving some gaps.

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, clear sentence that front-loads the core action without unnecessary words. It efficiently conveys the tool's purpose without redundancy, making it easy for an agent 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 mutation tool with no output schema, the description is minimal but functional. Annotations provide good behavioral coverage (non-destructive, idempotent), but the description lacks details on outcomes (e.g., what happens after disassociation) or error handling. It's adequate given annotations but incomplete for full agent understanding.

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% (one of two parameters documented). The description doesn't add any parameter-specific information beyond what's in the schema (e.g., it doesn't explain AssociationId format or region implications). With moderate schema coverage, the description doesn't compensate for gaps, resulting in a baseline score.

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 verb ('Disassociate') and resource ('route table'), specifying the targets ('subnet or internet gateway or virtual private gateway'). It distinguishes from siblings like 'associate-route-table' by indicating the opposite action, though it doesn't explicitly compare them. The purpose is specific but lacks explicit sibling differentiation.

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 like 'replace-route-table-association' or 'delete-route-table', nor does it mention prerequisites (e.g., existing association). It only states what the tool does without context for selection, leaving the agent to infer usage from the action name alone.

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