Vultr MCP

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It effectively describes key traits: it's a write operation ('Create'), specifies that it returns user information including an API key under certain conditions, and outlines permission options via the ACLs list. However, it doesn't mention potential side effects, error conditions, or authentication requirements, leaving some behavioral aspects uncovered.

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 well-structured with clear sections ('Args:', 'Returns:') and uses bullet points for the ACLs list, enhancing readability. It's appropriately sized for a tool with 7 parameters, though the ACLs enumeration is lengthy but necessary for completeness. Every sentence adds value, with no redundant information.

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 creation tool with 7 parameters, 0% schema coverage, no annotations, but an output schema present, the description does a strong job. It covers all parameters in detail, explains the return value, and provides context for key options like service users and permissions. The output schema existence means the description doesn't need to detail return structure, but it still mentions what's included (e.g., API key), making it largely complete for 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?

Given 0% schema description coverage, the description compensates fully by providing detailed semantics for all 7 parameters. It explains each parameter's purpose (e.g., 'email: User's email address'), clarifies boolean defaults indirectly through context, and enumerates available ACL permissions with descriptions, adding significant value beyond the bare schema.

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 specific action ('Create a new user') and identifies the resource ('user'), making the purpose immediately evident. It distinguishes itself from sibling tools like 'create_user' by being a more generic 'create' tool, but the description explicitly clarifies it's for user creation, preventing confusion with other creation tools in the list.

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 through the parameter explanations (e.g., 'service_user: Create as service user (API-only, no portal login)'), suggesting when to set certain flags. However, it lacks explicit guidance on when to use this tool versus alternatives like 'setup_service_user' or 'setup_standard_user' from the sibling list, leaving the agent to infer context from parameter semantics alone.

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