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

No annotations are supplied, so the description carries the full behavioral burden. It discloses the x402 payment model ("5 free trial calls per signed wallet"), which is genuinely useful, but says nothing about whether the lookup hits a network, what the response contains, or error behavior for unknown codes.

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?

Two short, front-loaded sentences with no filler. The "BIC Lookup:" prefix mildly restates the tool name, but the rest is efficient and the payment caveat is clearly placed.

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 two-parameter lookup with no annotations and no output schema, the description omits the relationship between the inputs and any indication of what is returned. An agent could not reliably construct a valid call from this definition alone.

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 0% across two parameters, so the description must compensate and does not. It never explains the difference between `bic` and `code`, whether they are alternatives or must be combined, or why neither is required despite the tool's single purpose.

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?

States a specific verb and resource: "Look up a bank BIC/SWIFT code." An agent can tell this is a lookup of banking identifier data. It does not distinguish itself from nearby siblings like x402-is-swift-bic (validation) or x402-swift-code, so it stops short of a 5.

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 on when to use this versus the several sibling BIC/SWIFT tools, and no prerequisites or exclusions are stated. The only context offered is a pricing note, which does not help an agent choose this tool over alternatives.

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