Rebillia MCP Server

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

With no annotations provided, the description carries the full burden. It discloses key behavioral traits: the tool performs a write operation ('Create'), specifies the HTTP method (POST), and notes important constraints like amount in cents and weight requirements for physical categories. However, it does not mention permissions, rate limits, or error handling, leaving gaps for a mutation tool.

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 front-loaded with the core purpose and key details (amount in cents, required parameters), followed by optional parameters. It avoids redundancy but includes some API-specific details (POST endpoint) that may not be essential for tool selection. Overall, it is efficient with minimal waste.

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?

Given the complexity (10 parameters, mutation tool) and no annotations or output schema, the description is moderately complete. It covers the action, key constraints, and parameter roles, but lacks information on return values, error cases, or integration with sibling tools. This is adequate but has clear gaps for effective agent use.

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 100%, so the schema already documents all parameters thoroughly. The description adds minimal value beyond the schema, such as emphasizing the amount in cents and noting default values (e.g., qty default 1). It does not provide additional syntax or format details, aligning with the baseline for high schema coverage.

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 ('Create a charge or credit for a customer'), identifies the resource ('customer'), and distinguishes it from siblings like 'charge_invoice' or 'list_customer_charges_credits' by focusing on creation rather than listing or invoicing. It explicitly mentions the HTTP method and endpoint, reinforcing the action.

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 specifying required and optional parameters, but does not explicitly state when to use this tool versus alternatives like 'charge_invoice' or 'create_invoice'. It provides context on parameter constraints (e.g., amount in cents, weight required for physical category) but lacks explicit guidance on scenarios or prerequisites.

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