vat_return

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

With no annotations, the description carries the full burden; it does signal a read-style retrieval and tells the agent what fields come back, including the filed flag. It does not disclose the data source (sheet vs e-fatura), permissions, or what happens for a quarter that has not been created/indexed.

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?

A single front-loaded sentence with no filler; every clause names a concrete piece of returned data. The phrasing 'as the sheet shows them' is slightly vague but does convey that values mirror the sheet layout.

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?

No output schema exists, so the description must describe return values — and it does, listing box 61, boxes 90-96, and filing status. What remains missing is the source of truth and the behavior for unfiled or non-existent quarters, which matters for a two-parameter lookup.

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 compensation is required. The description clarifies the quarter parameter domain (Q1-Q4) and ties it to a specific reporting period, but says nothing about the required 'year' parameter or its relationship to a year sheet.

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 names a specific resource — the Declaração Periódica boxes for a given quarter — and enumerates the contents (box 61 credit carried over, boxes 90-96 results, filed status). This clearly separates it from siblings like vat_codes (code lists) and mark_filed (mutation), though the retrieval verb is only implied by 'as the sheet shows them'.

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?

There is no statement of when to call this versus alternatives such as vat_codes or mark_filed, and no prerequisites (e.g. whether the year must be indexed first). The agent must infer that this is the read path for a quarter's return.

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