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 that the operation is a GET request (implying read-only) and returns paginated records, which is useful behavioral context. However, it doesn't mention potential rate limits, authentication requirements, error conditions, or what 'paginated external invoice records' specifically includes (e.g., fields, structure).

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 concise and well-structured in three sentences: purpose statement, API endpoint, and parameter mention. Each sentence adds value without redundancy. It could be slightly more front-loaded by integrating the parameter info into the purpose statement, but it's efficient overall.

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 read operation with no annotations and no output schema, the description provides adequate basics: purpose, endpoint, and pagination behavior. However, it lacks details on response format, error handling, or authentication needs, which would be helpful given the absence of structured metadata. It's minimally viable but has clear gaps.

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 fully documents all 4 parameters (subscriptionId, include, pageNo, itemPerPage). The description mentions these parameters as 'optional: include, pageNo, itemPerPage' but doesn't add meaningful semantic context beyond what's in the schema (e.g., what 'include' might accept, typical pagination behavior). Baseline 3 is appropriate when schema does the heavy lifting.

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 tool's purpose: 'List e-commerce orders (external invoices) linked to a subscription.' It specifies the verb ('List'), resource ('e-commerce orders/external invoices'), and scope ('linked to a subscription'). However, it doesn't explicitly differentiate from sibling tools like 'list_external_invoices' or 'get_subscription_invoices', which would be needed for a perfect score.

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 context by mentioning it's for listing external invoices for a specific subscription, but it doesn't provide explicit guidance on when to use this tool versus alternatives like 'list_external_invoices' (which might list all external invoices) or 'get_subscription_invoices' (which might list internal invoices). No exclusions or prerequisites are mentioned.

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