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

Annotations already declare readOnly/idempotent/non-destructive, so the safety profile is covered. The description adds genuinely useful behavioral context: status semantics (RECEBIDO = pago here, unlike its literal meaning), the shared status set with receivables, and the same item shape as list_receivables. Does not cover pagination defaults or response shape, hence not a 5.

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?

One dense paragraph, front-loaded with the purpose, then filters, then the sibling differentiation. Slightly packed but every clause adds information; nothing is redundant filler.

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, yet the description compensates by stating the item format mirrors list_receivables. Combined with the status enum, date semantics, and default listing behavior, an agent has enough to call it correctly. The unexplained 'account' parameter and absent pagination default are the remaining gaps.

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 coverage is 0% and the schema has no enums, so the description carries the load. It documents 5 of 6 params with date format (YYYY-MM-DD), omission behavior, and the full status enum list — critical since the schema provides none. It omits any explanation of the 'account' parameter, so not a 5.

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?

Specific verb (Lista) plus resource (contas a pagar / parcelas de despesa), and explicitly distinguishes itself from list_receivables by stating these are expenses ('parecido com list_receivables, mas são despesas'). An agent can tell it apart from the sibling without opening the schema.

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?

Gives concrete filter context and default behavior ('se omitidas, lista todas'), and routes away from list_receivables. It stops short of explicit when-not-to-use conditions, but the payables-vs-receivables framing gives clear selection guidance.

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