Generate Random IBAN

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

No annotations, so the description carries the full burden and does most of it: it discloses randomness, the ISO 13616/MOD-97 validity guarantee, correct national check digits 'where the country has them', and the critical caveat that generated IBANs were never issued by a bank. It omits return shape and any determinism/rate-limit behavior.

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 dense sentences with zero filler; the validity guarantee and the payment prohibition are both front-loaded where an agent will read them.

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 annotations and no output schema, the description should say what comes back (single string vs. array when count > 1). It covers behavior well but leaves the return contract unstated, which matters for a tool whose count parameter ranges 1-100.

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 67%; country and realistic are well documented in the schema, and the description only echoes 'for a country' and 'one or more' (count). It adds no meaning beyond the schema for any parameter, which is the expected baseline at this coverage level.

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?

States a specific verb (generate) and resource (random, structurally valid ISO 13616 / MOD-97 test IBANs) with clear scope qualifiers. The 'generate' verb cleanly separates it from sibling validate_iban and list_countries without needing to name 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?

Frames the use case explicitly as test data ('test IBANs') and gives a hard prohibition ('never use them for payments'), which is genuine when-not guidance. It stops short of routing to siblings (e.g. use validate_iban to check a real IBAN), so it isn't a full 5.

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

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

With no annotations, the description carries the full behavioral burden, and it does disclose the return contents (code, name, IBAN length) for what is evidently a read-only lookup. However it says nothing about whether the list is static or dynamic, its size, ordering, or caching behavior. Adequate but with gaps for an annotation-free 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?

A single front-loaded sentence with no filler; the resource and its return shape are stated immediately and nothing is redundant.

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?

No output schema exists, so the description usefully names the return fields (code, name, IBAN length). For a zero-parameter, low-complexity lookup this is nearly sufficient; only the absence of any indication of list size or stability keeps it from a 5.

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 tool takes zero parameters, so per the baseline this scores 4. The description adds no parameter detail, and none is needed.

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?

States a specific verb+resource ('List all countries') and adds scope ('supported for IBAN generation') plus the returned fields, which clearly separates it from generate_iban and validate_iban. It stops short of naming those siblings explicitly, so 4 rather than 5.

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 phrase 'supported for IBAN generation' implies the context in which an agent would need this list, but there is no explicit when-to-use statement, no exclusions, and no named alternatives. Usage is only inferable from the surrounding IBAN tools.

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

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

No annotations are supplied, so the description carries the full burden. It usefully discloses the validation criteria (MOD-97, length, country support), which is more than a bare 'validate' statement, but it says nothing about what happens on failure, whether a result is a boolean or an error list, or any auth requirements. Partial coverage of a low-risk read operation.

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?

A single front-loaded sentence that leads with the action and immediately lists the three checks. No filler or redundancy.

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 one-parameter, no-output-schema validation tool the description is close to sufficient, but it never states the shape of the result (pass/fail boolean vs. error details), which is the key thing an agent needs to interpret the call. No annotations exist to fill that gap.

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 100% and the single parameter is fully documented in the schema, including the 'spaces are ignored' normalization. The description adds no syntax, format, or IBAN example beyond what the schema already provides, so the baseline of 3 applies.

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 names a specific verb (Validate) and resource (IBAN) and enumerates the exact checks performed: MOD-97 checksum, expected length, and country support. The verb inherently separates it from the sibling generate_iban, so an agent can select it without inspecting the schema.

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 verb — validate when you need to check an IBAN — but there is no explicit when/when-not statement and no routing to alternatives such as generate_iban or list_countries. Adequate but leaves the agent to infer the trigger context.

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