AWS MCP Server

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

Annotations provide critical hints (destructiveHint: true, readOnlyHint: false, etc.), but the description adds minimal behavioral context. It doesn't explain the destructive nature beyond annotations, potential costs, time to provision, or error conditions. However, it doesn't contradict annotations, so it earns a baseline score for not undermining structured data.

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, efficient sentence that front-loads the core purpose without unnecessary words. It directly communicates the tool's function, making it easy to parse and understand 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 complex, destructive tool with 2 parameters (one nested with many sub-properties), 50% schema coverage, and no output schema, the description is insufficient. It lacks details on behavioral outcomes, error handling, or integration context, leaving significant gaps for an AI agent to understand full usage.

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?

With schema description coverage at 50%, the description doesn't compensate by explaining parameters beyond the schema. It mentions 'region' and implies 'DBInstanceArgs' but adds no details on required fields, defaults, or constraints. The schema handles most parameter documentation, so this meets the baseline for adequate 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 clearly states the action ('Create') and resource ('new RDS DB instance') with geographic context ('in the given region'). It distinguishes from siblings like 'update-db-instance' and 'delete-db-instance' by specifying creation, though it doesn't explicitly mention these alternatives.

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 is provided on when to use this tool versus alternatives like 'update-db-instance' or 'list-db-instances', nor does it mention prerequisites such as AWS credentials or region availability. The description only states what it does without contextual usage advice.

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