Validate Turkish IBAN

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

Annotations already cover readOnly/idempotent/closed-world, so the bar is lower; the description still adds real value by naming the mod-97 algorithm, the TCMB participant list as the bank source, and 'Offline', which tells the agent no network call or rate limit applies. It stops short of saying what happens on an invalid IBAN (thrown error vs. falsy result).

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?

Two tight sentences, no filler, with the core action first and the supplementary detail (bank identification, offline) trailing. Nothing to trim.

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?

With no output schema, the description should sketch the return shape, and it only hints that a bank name comes back alongside validity. For a one-parameter validation tool with annotations carrying the safety profile, it is adequate but leaves the response contract ambiguous.

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% for the single `iban` parameter, but the description only implies the constraint ('Turkish IBAN') without specifying expected format — country prefix, length, whether spaces or lowercase are tolerated.

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?

Uses a specific verb+resource ('Validate a Turkish IBAN') and adds two distinguishing details: mod-97 checksum and bank lookup via the TCMB participant list. Sibling validators are validate_tckn/validate_vkn, and the 'Turkish IBAN' scoping is enough to tell them apart, though the description never names them.

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?

Usage is implied by the name and the 'Turkish IBAN' scope, but there is no explicit statement of when to reach for this versus validate_tckn/validate_vkn, nor any prerequisite (e.g. input must be a TR-prefixed 26-char IBAN).

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