hostinger-api-mcp

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

No annotations are provided, so the description carries full burden. It mentions this is for configuring the 'primary payment method for future orders,' which implies a mutation with downstream effects, but fails to disclose critical behavioral traits: whether this requires specific permissions, if changes are reversible, potential rate limits, or what happens if the payment method ID is invalid. For a mutation tool with zero annotation coverage, this is a significant 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 efficiently structured in two sentences: the first states the core purpose, and the second provides usage context. Every sentence earns its place with no wasted words, making it front-loaded and easy to parse quickly.

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 this is a mutation tool with no annotations and no output schema, the description is incomplete. It lacks details on behavioral aspects (e.g., permissions, reversibility), error handling, or what the tool returns upon success. While the purpose is clear, the context for safe and effective use is insufficient for a tool that modifies account settings.

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 parameter 'paymentMethodId' fully documented in the schema as 'Payment method ID' of type integer. The description does not add any additional meaning beyond this, such as how to obtain valid IDs or format requirements. With high schema coverage, the baseline score of 3 is appropriate, as 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 ('Set the default payment method') and target resource ('for your account'), making the purpose immediately understandable. It distinguishes from obvious siblings like billing_deletePaymentMethodV1 by focusing on configuration rather than deletion. However, it doesn't explicitly differentiate from all billing siblings, such as billing_getPaymentMethodListV1, which is why it doesn't reach 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 second sentence provides implied context for when to use it ('to configure the primary payment method for future orders'), suggesting it's for setting up payment defaults. However, it lacks explicit guidance on when not to use it (e.g., for initial setup vs. updates) or alternatives (e.g., using billing_getPaymentMethodListV1 first to verify available methods), leaving some ambiguity.

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