CoinMarketCap MCP Server

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It states this is a read operation ('Returns information'), implying it's non-destructive, but doesn't cover critical aspects like authentication needs, rate limits, error handling, or response format. For a tool with 5 parameters and no output schema, this leaves significant gaps in understanding how it behaves.

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, clear sentence that efficiently conveys the core purpose without unnecessary words. It's front-loaded with the key action and resource, making it easy to parse. Every part of the sentence earns its place by directly stating what the tool does.

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 complexity (5 parameters, 1 required), no annotations, and no output schema, the description is incomplete. It doesn't explain the tool's behavior, parameter usage, or return values, leaving the agent with insufficient information to use it effectively. For a data-fetching tool in a rich API context, more detail is needed to be considered complete.

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?

Schema description coverage is 0%, meaning none of the 5 parameters (id, start, limit, convert, convert_id) are documented in the schema. The description adds no parameter information beyond implying 'id' is required for a single category. It doesn't explain what 'start' or 'limit' do (e.g., pagination), what 'convert' or 'convert_id' mean (e.g., currency conversion), or their formats, failing to compensate for the low coverage.

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 information') and resource ('about a single coin category on CoinMarketCap'), making the purpose understandable. However, it doesn't distinguish this tool from sibling tools like 'cryptoCategories' or 'getCryptoMetadata', which likely return similar or overlapping data, so it doesn't achieve full 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. It doesn't mention siblings like 'cryptoCategories' (which might list multiple categories) or 'getCryptoMetadata' (which could include category details), leaving the agent with no context for selection. This lack of comparative information reduces usability.

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