AWS FinOps MCP Server

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

With no annotations provided, the description carries full burden for behavioral disclosure. It states the tool returns recommendations but doesn't describe what types of recommendations, how they're generated, whether authentication is required (though parameters imply AWS credentials), or any rate limits or side effects. This is inadequate for a tool with AWS integration.

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 well-structured with clear sections for purpose, arguments, and returns. It's appropriately sized for a 6-parameter tool, though the parameter explanations are minimal and could be more informative.

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 the tool's complexity (AWS integration, 6 parameters) and the presence of an output schema (which covers return values), the description is partially complete. It explains the basic purpose and parameters but lacks crucial context about authentication, recommendation types, and usage scenarios that would help an agent use it effectively.

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?

The description lists all 6 parameters with brief explanations, but the schema description coverage is 0%, so the description compensates somewhat. However, it doesn't explain parameter relationships (e.g., that credentials parameters are mutually exclusive alternatives) or provide format examples, leaving significant gaps.

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 tool's purpose: 'Get EC2 instance cost optimization recommendations.' It specifies the resource (EC2 instances) and the action (get recommendations), but doesn't explicitly differentiate from sibling tools like 'get_cost_optimization_ebs' or 'get_cost_optimization_rds' beyond the EC2 focus.

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 sibling tools like 'get_all_cost_optimization_recommendations' or 'find_underutilized_ec2_instances', nor does it specify prerequisites or appropriate contexts for use.

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