Vultr MCP

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

No annotations are provided, so the description carries the full burden. It describes a read operation ('List') and mentions 'Smart identifier resolution,' which adds some behavioral context about input handling. However, it lacks details on permissions required, rate limits, pagination, error conditions, or what 'Combined list' entails (e.g., format, sorting). For a tool with no annotations, this is insufficient to fully inform an agent about its behavior.

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 and front-loaded: the first sentence states the purpose, followed by key behavioral context (identifier resolution), and then structured sections for Args and Returns. Every sentence adds value, with no wasted words. It could be slightly more concise by integrating the Args section into the main text, but overall it's efficient and well-structured.

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 the tool's low complexity (one parameter, read-only operation), the description is mostly complete. It explains the purpose, parameter semantics, and return value ('Combined list of VPCs and VPC 2.0 networks'). Since an output schema exists, the description doesn't need to detail return values further. However, with no annotations, it could benefit from more behavioral context (e.g., error handling), but for this simple tool, it's adequate.

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?

The input schema has 0% description coverage, with one parameter 'instance_identifier' of type string. The description compensates fully by explaining the parameter's semantics: 'Instance label, hostname, or ID' and 'Smart identifier resolution: Use instance label, hostname, or ID.' This adds crucial meaning beyond the schema, clarifying what the parameter accepts and how it's resolved, which is essential for correct tool invocation.

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: 'List all VPCs and VPC 2.0 networks attached to an instance.' It uses a specific verb ('List') and identifies the resources (VPCs and VPC 2.0 networks) with their relationship to an instance. This distinguishes it from siblings like 'list_vpc2' (which likely lists all VPCs) or 'get_network_info' (which might provide general network information).

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 by specifying 'Smart identifier resolution: Use instance label, hostname, or ID,' which suggests when to use this tool (when you have an instance identifier). However, it does not explicitly state when to use it versus alternatives (e.g., compared to 'list_attached' or 'list_unattached' from siblings), nor does it provide exclusions or prerequisites. The guidance is present but limited to parameter usage.

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