CryptoDataAPI 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 describes what data is returned (market cap, flow data, per-stablecoin breakdown) and the interpretation of that data, but doesn't mention technical behaviors like rate limits, data freshness, error conditions, or authentication requirements. The description adds value by explaining the economic interpretation but lacks operational details.

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 perfectly front-loaded with the core purpose in the first clause, followed by explanatory context and detailed output information. Every sentence adds value: the first states what the tool does, the second explains why it matters, the third provides interpretation guidance, and the fourth details the return data structure. Zero wasted words.

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 parameterless tool with no output schema, the description provides excellent context about what data is returned and how to interpret it. It explains the economic significance and lists the specific data points (total market cap, 14-day/90-day flows, per-stablecoin breakdown). The main gap is the lack of output format details, but given the tool's relative simplicity, the description is quite 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?

The tool has 0 parameters with 100% schema description coverage, so the baseline is 4. The description appropriately doesn't waste space discussing parameters that don't exist, which is efficient and correct for a parameterless tool.

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 specific verbs ('Get stablecoin market cap and flow data') and resource ('stablecoin'). It distinguishes itself from sibling tools by focusing specifically on stablecoin metrics rather than other crypto data like BTC cycles, ETF flows, or market health indicators.

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 clear context for when to use this tool ('a proxy for capital entering or leaving crypto') and explains the significance of the data ('Rising stablecoin market cap signals new capital inflows (bullish). Declining market cap signals capital outflows (bearish)'). However, it doesn't explicitly state when NOT to use it or name specific alternatives among the sibling tools.

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