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 for behavioral disclosure. It states this is a creation operation (implying mutation) but provides no information about permissions required, whether the operation is idempotent, what happens on duplicate SKUs, rate limits, or what the response contains. For a mutation tool with zero annotation coverage, this leaves significant behavioral gaps.

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 brief (two sentences) and front-loaded with the core purpose. The second sentence efficiently lists parameter groupings. However, including the HTTP endpoint ('POST /products') adds implementation detail that doesn't help tool selection and could be considered extraneous.

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 mutation tool with no annotations and no output schema, the description is incomplete. It doesn't explain what happens after creation (e.g., returns product ID), error conditions, or system behavior. Given the complexity of product creation in what appears to be a billing/subscription system, more contextual information would be valuable for proper tool invocation.

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 5 parameters with their types and required status. The description adds marginal value by grouping parameters as 'Required' and 'Optional', but doesn't provide additional semantic context beyond what's in the schema (e.g., format expectations for SKU, category constraints, or internalProductId purpose).

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 ('Create a product') and resource ('product'), making the purpose immediately understandable. It distinguishes from siblings like 'update_product' or 'delete_product' by specifying creation. However, it doesn't explicitly differentiate from other creation tools like 'create_customer' or 'create_invoice' beyond the resource name.

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. It doesn't mention prerequisites (e.g., whether a customer must exist first), nor does it clarify when to use 'create_product' versus 'link_external_product' or other product-related tools. The HTTP method mention ('POST /products') is implementation detail, not usage guidance.

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