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

With no annotations, the description carries the burden of behavioral disclosure. It explicitly states pure local computation, microsecond latency, and deterministic results, which is helpful. However, it does not describe error handling, what happens for invalid inputs, the exact response structure, or any assumptions (e.g., country-specific rules). It goes beyond trivial, but leaves gaps.

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 concise and well-structured: first sentence lists the types and auto-detection, second sentence highlights value-added resolution and performance. No repetition of schema info, and every sentence adds substance. It is front-loaded with the core purpose.

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 handles multiple data types and has no output schema, so the description should clarify return format. It hints at extra details (bank, province, GS1 prefix) but does not describe the overall response structure (e.g., valid flag, details object) or error behavior. Given the breadth of inputs, this is a notable gap for an agent to know what to expect.

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 input schema already describes both parameters thoroughly (coverage 100%), including type enum and value constraints. The description adds that type is optional and auto-detected, which reinforces the schema's own description. It does not add significant new parameter-level details beyond what schema already provides, so a baseline score 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 the tool validates a wide range of Turkish identifiers (national ID, tax number, IBAN, licence plate, etc.) from a single endpoint with auto-detection. It also lists additional capabilities ('resolves the bank behind an IBAN, the province behind a licence plate...'), making its purpose distinct from sibling tools like iban_validate or tin_validate.

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 a general-purpose, one-stop-shop role ('from one endpoint') but does not explicitly state when to prefer this tool over dedicated validators, nor when not to use it. It mentions auto-detection as a convenience, but lacks explicit comparisons or exclusions (e.g., 'if you need only IBAN, use iban_validate').

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