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 but offers minimal behavioral insight. It mentions the HTTP method (GET) and optional pagination parameters, but doesn't disclose critical traits like whether it's read-only (implied by 'list'), rate limits, authentication needs, error handling, or response format. This leaves significant gaps for agent understanding.

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 two sentences: one stating the core purpose and endpoint, another listing parameters. It's front-loaded with essential information, though the parameter list could be more integrated into the flow rather than appended as a fragment.

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 list operation with 6 parameters, no annotations, and no output schema, the description is incomplete. It lacks details on response structure (e.g., paginated list format), error conditions, authentication requirements, and usage context. While the schema covers parameter basics, the overall tool behavior remains underspecified 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%, providing clear documentation for all 6 parameters. The description adds marginal value by noting that productId is a URI reference and listing optional parameters by name, but doesn't explain their practical use (e.g., what 'include' attributes are available, valid values for 'sortBy'). Baseline 3 is appropriate given the 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 action ('List product rate plans') and resource ('for a product'), making the purpose unambiguous. It distinguishes from siblings like 'get_product_rate_plan' (singular) and 'list_products' (different resource), though it doesn't explicitly contrast with 'list_product_rate_plan_charges' (related but distinct).

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?

No guidance is provided on when to use this tool versus alternatives like 'get_product_rate_plan' (for a single rate plan) or 'list_product_rate_plan_charges' (for charges within rate plans). The description mentions the required productId but lacks context on prerequisites or typical use cases.

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