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

Beyond annotations, the description discloses the irreversible nature of payout_address, the need for full-address user confirmation, CPF/CNPJ requirements under Central Bank rules, the 24h provider hold above the instant band, and the R$6,000/day refusal threshold. It also documents idempotent retry behavior and the three error modes. The description is consistent with the annotations, which already signal mutating, idempotent, destructive 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 long, but it is well-organized and front-loaded with the most critical warnings. Every paragraph addresses a distinct concern: prerequisites, return artifacts, irreversibility, payer rules, pre-flight checks, idempotency, compliance, and error handling. It loses one point for minor redundancy with schema content, such as restating that amount_cents is an integer in cents.

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 description covers the essential return values (QR code, copy-and-paste string), hold behavior, and error actions. However, because there is no output schema, an agent would benefit from an explicit list of key response fields such as charge ID and expiry, which would support follow-up calls like lunium_get_pix_charge or lunium_verify_pix_payment.

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?

With 100% schema coverage, the baseline is 3, but the description adds materially above the schema: it warns that amount_cents is an integer in cents (not reais/float), that payout_address must come from user/config and must be confirmed in full, and that external_id enables safe retries. It also clarifies that payer_tax_number must be the real payer, not a placeholder or third party.

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 opens with a clear verb-object pair — 'Creates a PIX charge' — and specifies the returned artifact (QR code and copy-and-paste string) and the outcome (crypto delivered to payout_address when paid). The title reinforces the behavior with 'IRREVERSIBLE', and the scope is distinct from sibling tools like lunium_get_pix_charge.

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?

Explicitly tells the agent to call lunium_check_payer_limit first and explains how the payer band affects delivery (instant vs 24h hold). It also gives exclusion rules: don't create a new charge while one for the same intent is pending/delayed, and don't describe the flow as anonymous. Error actions (acao=corrigir/esperar/repetir) tell the agent what to do next.

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