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

No annotations are provided, so the description carries the full burden of explaining behavior. It reveals nothing about return format, whether the index is zero-based or one-based, whether it returns the first/leftmost occurrence, or what happens with an empty input. This is a complete disclosure failure.

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 extremely short, but this is under-specification rather than disciplined conciseness. It mirrors the 'Process' calibration example: one tautological line that conveys no usable information beyond the tool name.

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?

With no annotations, no output schema, no parameters, and a one-line tautological description, the definition is completely inadequate. An agent cannot determine what input this tool acts on, what it returns, or how to invoke it correctly.

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 input schema has zero parameters and 100% coverage, so there are no parameter semantics the description must clarify. Per the zero-parameter baseline, this dimension is not penalized, though the description adds no meaningful parameter context.

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 'Find Min Index: Find min index.' is a pure tautology—it restates the tool name and title without adding any operationally distinct meaning. It does not specify what collection or values are searched, what an 'index' refers to, or how this differs from siblings like x402-find-min, x402-find-max-index, or x402-find.

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?

There is no guidance whatsoever about when to use this tool versus alternatives. With sibling tools such as x402-find-min, x402-find-max-index, and many array/search utilities, an agent has no basis for selecting this tool.

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