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 and does well by disclosing key behavioral traits: it's a mutation operation ('Set'), has side effects ('Creates company currency if needed'), and specifies a failure condition ('Fails if there are invoices with that currency'). It doesn't mention authentication needs, rate limits, or response format, but covers essential mutation behavior adequately.

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 in three concise sentences that each earn their place: states the purpose, specifies the required parameter, and discloses important behavioral constraints. No wasted words, and key information is front-loaded with the core action.

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 single-parameter mutation tool with no annotations and no output schema, the description is reasonably complete: it explains what the tool does, what parameter is needed, and important behavioral constraints. It could benefit from mentioning response format or success indicators, but covers the essential context given the tool's complexity.

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%, with the single parameter 'currencyId' documented as 'Global currency ID (required)'. The description adds minimal value beyond the schema, only restating that 'currencyId' is required and is a 'global currency ID'. No additional syntax, format, or semantic details are provided beyond what's in the schema.

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 ('Set the company default currency'), identifies the resource ('company default currency'), and distinguishes from siblings like 'create_currency' (creates new currency) and 'get_default_currency' (reads current default). The verb 'Set' is precise and differentiates from creation or retrieval operations.

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 ('Set the company default currency') and mentions a key failure condition ('Fails if there are invoices with that currency'), which helps guide usage. However, it doesn't explicitly state when NOT to use it or name specific alternatives among the many sibling tools, though the purpose naturally distinguishes it from most siblings.

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