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 address authentication requirements, rate limits, error conditions, or whether the data is real-time or cached. The 'Returns' section adds minimal value by restating the purpose with slightly different wording.

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 but could be more efficiently structured. The first sentence clearly states the purpose, but the 'Returns:' section is somewhat redundant with the first sentence. The two-sentence structure is acceptable but not optimally front-loaded with the most critical 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 tool with no annotations and no output schema, the description is insufficiently complete. It doesn't explain what 'service breakdown' means, what format the data returns in, whether authentication is required, or any limitations. Given the complexity of usage and cost data, more context about the output structure and behavioral constraints would be helpful.

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 parameters with 100% schema description coverage, so the baseline is 4. The description appropriately doesn't discuss parameters since none exist, and the 'Returns' section provides some context about the output format ('service breakdown'), which adds value beyond the empty 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 tool's purpose: 'Get last month usage and cost summary' with the specific resource being 'usage and cost summary' and temporal scope 'last month'. It distinguishes from siblings like 'get_current_month_summary' by specifying the time period, but doesn't explicitly differentiate from similar tools like 'get_monthly_usage_summary' or 'analyze_costs'.

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 'get_current_month_summary', 'get_monthly_usage_summary', 'analyze_costs', and 'get_cost_breakdown_by_service', there's no indication of when this specific tool is appropriate versus those other options. The description only states what it does, not when to choose it.

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