CoinMarketCap MCP Server

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

With no annotations provided, the description carries full burden for behavioral disclosure. It states this is a read operation ('Returns'), but doesn't mention authentication requirements, rate limits, data freshness, or what 'latest' means (e.g., real-time vs. periodic updates). For a tool with zero annotation coverage, this leaves significant gaps in understanding 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 a single, efficient sentence that gets straight to the point with zero wasted words. It's appropriately sized for a simple data retrieval tool and front-loads the core functionality.

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 2 undocumented parameters, no annotations, and no output schema, the description is insufficiently complete. It doesn't explain what metrics are returned, how parameters affect results, or provide any context about data sources or limitations. For a tool in a crowded namespace with many sibling alternatives, more guidance is needed.

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 provides no information about the two parameters ('convert' and 'convert_id'), and with 0% schema description coverage, both parameters are completely undocumented. The description doesn't compensate for this gap by explaining what these parameters do or how they affect the returned metrics.

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 action ('Returns') and resource ('latest global cryptocurrency market metrics'), making the purpose immediately understandable. However, it doesn't differentiate from sibling tools like 'cmc100IndexLatest' or 'fearAndGreedLatest' that also return latest metrics for specific subsets, leaving some ambiguity about scope.

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 'cmc100IndexLatest' for index metrics and 'fearAndGreedLatest' for sentiment metrics, there's no indication of whether this tool is comprehensive or how it differs, leaving the agent to guess based on tool names alone.

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