list_vatex_codes

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

No annotations are present, so the description carries the behavioral burden. 'List' clearly signals a read-only operation and the source is stated, but there is no mention of output structure, ordering, or whether all codes are returned. The presence of an output schema mitigates this somewhat.

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?

One concise, front-loaded sentence with no filler. The verb, resource, and source are all stated economically.

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 zero-parameter list tool with an output schema, the description is essentially complete: it names the resource and the code-list source. The only minor gap is not referencing the sibling check_vatex_code for validation use cases, but this is not required for basic invocation.

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 has zero parameters and schema coverage is 100%, so there is nothing meaningful for the description to add. The baseline of 4 applies because parameter semantics are fully covered by the empty schema.

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 uses a specific verb ('List') with a concrete resource ('VATEX (VAT exemption reason) codes') and a precise source ('CEF EN 16931 code list'). This clearly distinguishes it from sibling check_vatex_code, which validates rather than lists.

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 imperative 'List' implies the tool is for enumerating VATEX codes, but there is no explicit guidance about when to use this tool versus check_vatex_code or other list/check siblings. No when-not or alternative routing is provided.

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