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

With no annotations provided, the description carries the full burden of behavioral disclosure. It fails completely — it does not state that this is a validation check, what input format is expected, what it returns, or any side effects. A completely opaque placeholder.

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?

While very short, the description is repetitive and under-specified — it repeats the tool name verbatim rather than conveying information. This is placeholder-level under-specification, not disciplined conciseness.

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 tool with no annotations and no output schema, the description is the only source of context, and it is completely inadequate. An agent cannot determine what input to provide, what the tool does, or what result to expect. The definition is unusable as written.

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 properties, so the baseline is 4 per the rubric. There are no parameters for the description to document, so it cannot add or subtract much here. However, it also fails to clarify how the tool receives its input (e.g., via the prompt), which slightly undermines usability.

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 'Is SWIFT BIC: Is SWIFT BIC' is a pure tautology — it simply restates the tool name with no verb, resource, or scope. It gives an agent no idea that this tool likely validates whether a value is a SWIFT BIC code, and it does nothing to distinguish itself from siblings like x402-swift-code or x402-bic-lookup.

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 on when to use this tool versus alternatives. The sibling list contains closely related tools (x402-swift-code, x402-bic-lookup, x402-iban-validate), but the description never mentions them or any selection condition.

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