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

Annotations already indicate read-only, idempotent behavior. The description adds that the tool uses 'OpenIBAN' as a data source and that spaces are stripped automatically (from schema), but does not disclose any additional behavioral traits beyond what annotations and schema provide.

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 a single, effective sentence that front-loads the verb and resource. It conveys the core functionality concisely with no wasted words.

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?

The tool is simple with one parameter and an output schema (not shown). The description mentions expected output fields (BIC/SWIFT, bank name, city). However, it lacks guidance on distinguishing from sibling IBAN tools, which slightly reduces completeness.

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 coverage is 100% and includes a description with format details and auto-stripping of spaces. The tool description adds no further meaning to the single parameter beyond what the schema already provides. With full schema coverage, a score of 3 is appropriate.

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 'Validate an IBAN number and get associated bank data', which is a specific verb+resource combination. However, it does not explicitly differentiate this tool from the sibling 'iban.banking.validate' tool, which likely has similar functionality.

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 tool versus alternatives. Despite having sibling tools like 'iban.banking.calculate' and 'iban.banking.validate', the description provides no context about when this tool is appropriate or not.

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