validate_iban

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

With no annotations, the description should disclose behavioral traits like handling of invalid input, return format, or external dependencies. It mentions 'check digit' but doesn't specify if the tool provides detailed error messages or simply a boolean. This is insufficient for a validation tool.

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 short and front-loaded with purpose, but the 'Parameters' section is redundant for a single parameter and could be removed. It is adequate but not optimally concise.

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 the presence of an output schema, the description need not detail return values. However, it lacks context on error handling and edge cases. For a validation tool, more completeness would be expected, even with an output schema.

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 description lists the parameter 'iban' with a brief explanation 'IBAN number to validate.' However, with 0% schema description coverage, it adds minimal extra meaning. No format, length, or examples are provided, leaving the agent to guess the expected input type.

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 the tool's purpose: 'Validate IBAN format and check digit for international bank accounts.' This provides a specific verb ('validate') and resource ('IBAN format and check digit'), distinguishing it from sibling validation tools like validate_json or validate_vat.

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?

No guidance is provided on when to use this tool versus alternatives. There is no mention of prerequisites, limitations, or scenarios where validation might fail. The description only explains what it does, not when to use it.

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