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 mentions the return type ('List of available CDN regions with details'), which adds some behavioral context, but fails to disclose critical traits like whether this is a read-only operation, if it requires authentication, rate limits, or error conditions. The description doesn't contradict annotations, but provides minimal behavioral insight.

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 brief and front-loaded, with the core purpose stated first. The second sentence about returns adds value without being redundant. However, it could be more structured (e.g., separating purpose from returns with formatting) and slightly more informative to improve clarity.

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 simplicity (0 parameters, no annotations, no output schema), the description is incomplete. It lacks context on authentication needs, rate limits, error handling, and how the returned list is structured (e.g., pagination, format). For a tool in a complex server with many siblings, more guidance would help an agent use it correctly.

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 tool has 0 parameters, and the input schema has 100% description coverage (though empty). The description doesn't need to explain parameters, so it appropriately avoids redundancy. A baseline of 4 is justified since there are no parameters to document, and the description doesn't introduce confusion.

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 with a specific verb ('Get') and resource ('list of available CDN regions'), making it immediately understandable. However, it doesn't explicitly differentiate from potential siblings like 'list_cdn_zones' or 'get_cdn_zone', which might provide overlapping or related information about CDN resources.

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. With many sibling tools related to CDN (like 'get_cdn_zone', 'list_cdn_zones', 'setup_cdn_for_website'), there's no indication of context, prerequisites, or exclusions to help an agent choose appropriately.

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