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

With no annotations, the description carries the full burden of behavioral disclosure. It adds a cost-related trait ('Free') and the validation algorithm, but does not disclose the return format (e.g., boolean vs. error details) or any other side effects. This is partial but not complete transparency.

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 sentence that conveys the purpose and the 'Free' attribute with no redundant information. It is appropriately sized for the tool's simplicity and front-loads the core action.

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 simple validation tool with one parameter and no output schema, the description gives the core purpose and algorithm but omits the result shape (true/false/error) and any required input format details. It is adequate for a basic understanding but not fully complete for confident invocation without external domain knowledge.

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 0% and the only parameter 'iban' is an undocumented string. The description implies the parameter is the Kazakhstan IBAN to validate, but it does not provide format examples, length constraints, or structural details beyond what the tool name already suggests. The description does not sufficiently compensate for the missing schema documentation.

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 with a specific verb ('Validate') and resource ('Kazakhstan IBAN'), and explicitly mentions the algorithm (ISO 7064 mod-97 + KZ structure). This distinguishes it from sibling validation tools like validate_iin, which likely targets a different identifier.

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?

The description implies the tool is for validating Kazakhstan IBANs but provides no explicit when-to-use or when-not-to-use guidance, nor does it reference alternatives. The context is clear enough for basic usage, but no exclusions or decision rules are offered.

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