Rebillia MCP Server

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

No annotations are provided, so the description carries full burden. It discloses the HTTP method (GET) and mentions pagination and include options, which adds useful behavioral context. However, it doesn't cover critical aspects like authentication requirements, rate limits, error conditions, or response format details. For a read operation with no annotations, this is a moderate disclosure gap.

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 appropriately sized with two sentences: one stating the purpose and endpoint, another detailing features. It's front-loaded with the core functionality. There's no wasted text, though it could be slightly more structured (e.g., separating endpoint from behavior).

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 no annotations, no output schema, and 4 parameters with full schema coverage, the description is moderately complete. It covers the basic operation and key features (pagination, include) but lacks details on authentication, error handling, response structure, and sibling tool differentiation. For a read tool in a complex API context, this is adequate 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 fully documents all parameters. The description adds minimal value by mentioning pagination and include (e.g., rateplan, rateplanCharge), which slightly elaborates on the include parameter's purpose. However, it doesn't provide additional syntax, format, or usage details beyond what the schema already states. 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 with 'List subscriptions for a customer', specifying the verb (list) and resource (subscriptions) with a target (customer). It doesn't explicitly differentiate from sibling tools like 'list_subscriptions' or 'get_subscription', but the customer-specific focus is implied. This is clear but lacks explicit sibling differentiation.

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 no guidance on when to use this tool versus alternatives. With siblings like 'list_subscriptions' (likely general listing) and 'get_subscription' (likely single subscription retrieval), there's no indication of when this customer-specific listing is preferred. The mention of pagination and include options is functional but doesn't address usage context.

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