list_payment_means_codes

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

No annotations are provided, so the description carries the burden of behavioral disclosure. It states the source and that it lists codes, which implies a read-only operation, but it does not disclose details like ordering, pagination, completeness, or whether code descriptions are included.

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 a single, dense sentence with no filler. It front-loads the core purpose and source immediately.

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?

This is a simple zero-parameter listing operation, and an output schema exists to describe return values. The description names the exact code list and scope, so an agent has enough information to invoke the tool correctly.

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 the schema already defines an empty object with additionalProperties false. The baseline for zero-parameter tools is 4; the description adds no parameter information because 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?

The description uses a specific verb ('List'), a precise resource ('UNCL4461 payment means codes'), and a clear source ('CEF EN 16931 code list'). It clearly differentiates from the sibling check_payment_means_code, which checks a single code rather than listing all codes.

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 the tool is used for enumerating payment means codes, but it does not explicitly state when to use this tool versus alternatives such as check_payment_means_code. The usage context is only implied by the list/check naming pattern among siblings.

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