list_invoices

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

With no annotations, the description carries the full burden for behavioral disclosure. It mentions the return items and a download action, but it omits important traits such as authentication prerequisites (e.g., requiring jcs_login), pagination behavior, and the exact field name for the attach URI (it is not listed among the item fields). This leaves operational gaps for the agent.

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, with the primary purpose in the first sentence and supporting details in the second. It is front-loaded, efficient, and every sentence contributes value.

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 with no params and no output schema, so the description does explain the main return fields (clinic, number, date, amount). However, it fails to mention the attach URI as an item field, which creates ambiguity for the download step. Pagination is not addressed, leaving some incompleteness.

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 input schema has zero parameters, so the description has no need to explain parameter meanings. The baseline for 0 params is 4, and the description does not introduce any parameter-related confusion.

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 states a specific verb and resource: 'Return invoices (Faturas) from the patient profile.' This clearly distinguishes it from sibling list tools like list_prescriptions and list_appointments, and the parenthetical clarifies the term in the target language.

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?

It provides clear context ('from the patient profile') and a concrete follow-up action ('Use download_document(uri) with the item's attach URI to download the PDF'). However, it does not explicitly mention when not to use this tool or compare it to alternatives, so it lacks explicit exclusions.

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