Lists available invoices for an authorized consumer unit and returns opaque invoice IDs to enable unambiguous PDF downloads.
Lista faturas disponíveis para uma UC autorizada e devolve fatura_id opaca para download inequívoco.
| Name | Required | Description | Default |
|---|---|---|---|
| uc | No | ||
| refresh | No |
| Name | Required | Description | Default |
|---|---|---|---|
No arguments | |||
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, covering the safety profile. The description adds meaningful context: it returns an opaque fatura_id for unambiguous download and restricts operation to 'UC autorizada', implying authorization requirements. This goes beyond the annotations and helps the agent understand the tool's 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?
The description is a single sentence with no redundancy. It front-loads the main action, specifies the scope, and includes the key return value. Every word earns its place; nothing is extraneous.
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?
The tool is simple, has an output schema (so return format is known), and annotations cover safety. The description explains the purpose and the opaque ID. However, the 'refresh' parameter is completely unexplained, and the description does not mention any pagination, filtering, or error behavior. Given the zero-coverage schema, the description leaves a notable gap regarding the refresh flag.
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 description coverage is 0%, so the description must compensate. It implicitly explains the 'uc' parameter via 'para uma UC autorizada', but it entirely omits the 'refresh' parameter. With two parameters and no schema descriptions, leaving one completely undocumented is a significant gap. The description only partially fulfills the compensation requirement.
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 clearly states the verb (listar), the resource (faturas), the scope (para uma UC autorizada), and the purpose (devolve fatura_id para download inequívoco). It distinguishes itself from siblings: listar_ucs lists UCs, and baixar_fatura downloads an invoice, whereas this tool lists invoices for a given UC and returns an opaque ID to enable unambiguous download.
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 usage context: you need an authorized UC to list invoices, and the returned fatura_id is intended for a subsequent download (baixar_fatura). It does not explicitly state when not to use this tool or mention alternatives, but the context is clear enough from the description and sibling names.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.