einvoice_providers

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It clearly states this is a read-only listing operation (safe, non-destructive), and informs the agent about return contents (identifiers, labels, country codes). The explicit enumeration of providers adds useful predictability. It doesn't describe pagination or response format, but as a zero-parameter enumeration endpoint with no output schema, the disclosure is reasonably complete.

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 two sentences and highly efficient: the first sentence states purpose and return content, the second enumerates the actual provider values. No wasted words. It could arguably be more concise, but the provider list is genuinely useful, actionable information rather than fluff.

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, read-only listing tool with no output schema, the description is nearly complete. It tells the agent what comes back (identifiers, labels, country codes) and enumerates the exact set of providers. The absence of an output schema is partly compensated by the provider enumeration. The only minor gap is not stating whether additional providers can be added or whether the list is cached/static.

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 description coverage is 100% (trivially, since there are no parameters to document). The baseline for 0 params is 4 per the rubric. The description does not need to explain parameters since none exist, and it appropriately avoids padding.

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 clear resource ('all available e-invoicing providers'). It explicitly states what is returned (identifiers, labels, country codes) and enumerates the actual provider values, distinguishing it clearly from sibling tools. The tool is well-differentiated from related tools like einvoice_submit, einvoice_config_list, and borderou_providers.

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 this is a discovery/enumeration tool used to know available providers, which is reasonably clear context. However, it doesn't explicitly state when to use this vs alternatives (e.g., einvoice_config_list, borderou_providers), nor does it mention that this is the prerequisite for configuring submissions. No explicit when-not or alternative guidance is provided.

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