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

The description goes beyond simple validation by disclosing a key behavior: it parses the structure (birth date/sex or registration) upon successful validation. It also adds the operational constraint that the service is free.

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 definition is highly concise, condensing the core function, its parsing capabilities, and its operational cost into a single, dense sentence that captures maximum value.

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?

Since there is no output schema, the description is highly complete by explicitly detailing the expected structural output: parsed birth date/sex or entity registration, giving the agent full context about the response.

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?

While the schema provides the 12-digit format, the description provides critical domain knowledge that the schema misses—namely, that the input serves two different functions (IIN for person, BIN for entity) and what those components parse into.

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 tool clearly states its function (validate Kazakhstan IIN/BIN) using specific terminology, distinguishing it from general validation tools like validate_kz_iban found in the sibling list.

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 provides operational context by stating it is 'Free,' but it lacks explicit guidance on when this specific checksum/parsing tool should be used versus other general validation methods.

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