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

readOnlyHint=true already declares the safety profile. The sentence 'Totals and PDF links are in the attributes' adds useful output context beyond annotations, but nothing is said about ordering, result caps, or default pagination 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?

Two short sentences, front-loaded with the resource and followed by filter scope and a return-value note. No filler, though the filter list is a bare inventory rather than a prioritized lead.

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?

With 12 optional parameters and no output schema, the note about totals and PDF links partially compensates. However, 'validation_status' is undocumented in both schema and description, and there is no guidance on how period, operation_date, and operation_date_from/to interact.

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 92%, so the schema (including enum meanings for kind and payment_status) already does the heavy lifting. The description merely names filter dimensions already present in the schema and adds no syntax, precedence, or combination rules.

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?

States a specific verb and resource ('List invoices') plus the scope distinction 'issued and received', which clarifies the tool returns both income and expense invoices. Sibling tools contain no other invoice-listing endpoint, so differentiation is implicit rather than required.

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 by enumerating filter dimensions, but never states when to use this versus quipu_get_invoice for a single record, nor that filters are combinable. No exclusions or preconditions are given.

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