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

No annotations are provided, so the description carries the behavioral burden. It usefully discloses that each call costs $0.005 USDC via x402 on Base, which is important invocation context, but it does not describe return format, error behavior, rate limits, or payment failure handling.

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 two compact sentences with the core purpose front-loaded and pricing information clearly appended. Every sentence earns its place with no redundant wording.

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 no annotations and no output schema, the description should carry more of the behavioral and return-value burden. It covers purpose and payment cost, but omits output shape, limit semantics, and payment/error mechanics, leaving moderate gaps for correct 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 description coverage is 100%, so the baseline is 3. The description adds meaningful semantics for vcpu and memory as minimum thresholds and clarifies region is optional, but it ignores the limit parameter and does not fully explain the type values beyond on-demand or spot.

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 states a specific resource and scope: cheapest AWS EC2 Linux instances meeting minimum vCPU and memory, with on-demand or spot pricing and optional region. It is clear enough to distinguish from a generic pricing tool, but it does not explicitly differentiate itself from siblings like cloudprice_gpu or cloudprice_instance.

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?

It gives clear usage context: use when you need the cheapest EC2 Linux instance satisfying at least the given vCPU and memory, with optional region and pricing type. It does not state when not to use it or name alternative sibling tools, so it falls short of full when/when-not guidance.

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