Rebillia MCP Server

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

With no annotations provided, the description carries full burden for behavioral disclosure. While it mentions the HTTP method (POST) and that this is a payment operation, it doesn't disclose critical behavioral traits like whether this is a destructive/mutative operation, authentication requirements, rate limits, error conditions, or what happens on success/failure. For a payment tool with zero annotation coverage, this leaves significant gaps.

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 efficiently structured with three sentences that each serve a distinct purpose: stating the action, providing parameter formatting guidance, and offering usage recommendations. It's front-loaded with the core purpose and avoids unnecessary verbiage, though it could be slightly more polished in sentence flow.

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?

For a payment processing tool with 3 parameters, 100% schema coverage, but no annotations and no output schema, the description provides adequate basic information about what the tool does and parameter formatting. However, it lacks crucial context about the operation's consequences, return values, error handling, and security implications that would be expected for a financial transaction tool.

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 schema description coverage is 100%, so the baseline is 3. The description adds valuable semantic context beyond the schema: it clarifies that 'amount' is in cents with a concrete example (5500 = $55.00), and provides usage guidance for 'paymentType' ('Use thirdPartyPaymentProvider for card/online'). This adds practical implementation guidance that enhances the schema's technical specifications.

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 clearly states the specific action ('Charge an invoice') and the payment methods involved ('card/online payment'), distinguishing it from sibling tools like 'void_invoice' or 'refund_transaction'. It provides a concrete verb+resource combination with payment context.

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 provides clear context about when to use this tool ('card/online payment') and offers specific guidance on parameter selection ('Use thirdPartyPaymentProvider for card/online'). However, it doesn't explicitly mention when NOT to use it or name alternatives like 'charge_invoice_external' from the sibling list.

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