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 of behavioral disclosure. While 'Get' implies a read-only operation, the description doesn't mention any behavioral traits like whether this requires authentication, what happens when no plans are available, whether results are cached, or if there are rate limits. For a tool with zero annotation coverage, this is inadequate.

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 with a clear purpose statement followed by structured Args and Returns sections. Every sentence earns its place, though the 'Returns' section is somewhat redundant given the presence of an output schema (which would document return values).

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 has an output schema (which handles return value documentation) and only one parameter with adequate documentation in the description, the description is reasonably complete for a simple retrieval tool. However, the lack of behavioral context (especially with no annotations) and missing usage guidelines relative to siblings are notable gaps.

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 description includes an 'Args' section that documents the single parameter 'plan_type' as an 'Optional plan type filter', which adds meaningful context beyond the schema (which has 0% description coverage and only shows the parameter is optional with string/null types). This adequately compensates for the low schema coverage by explaining what the parameter does.

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 states the tool's purpose ('Get the cheapest available plan') which is a clear verb+resource combination, but it doesn't distinguish this tool from potential siblings like 'compare_plans' or 'search_plans_by_specs' that might also involve plan comparisons. The purpose is understandable but lacks sibling differentiation.

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 siblings like 'compare_plans', 'get_plan', 'get_plan_by_type_and_spec', and 'search_plans_by_specs' available, there's no indication of when this specific cheapest-plan retrieval is preferred over those other plan-related tools.

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