Block MCP Server

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

No annotations are provided, so the description carries the full burden. It mentions 'real-time rates,' which hints at up-to-date data, but doesn't disclose critical behavioral traits such as rate limits, authentication needs, error handling, or whether the conversion is simulated or executes a trade. For a financial tool with zero annotation coverage, this leaves significant gaps in understanding its operation.

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 well-structured with a clear purpose statement followed by parameter details. It uses bullet-like formatting under 'Args:' for readability. While efficient, it could be slightly more concise by integrating the examples into the main text, but overall it's front-loaded and wastes no space.

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's complexity (financial conversion with 3 parameters), no annotations, and an output schema present (which handles return values), the description is moderately complete. It covers the purpose and parameters adequately but lacks behavioral details like execution implications or error cases, making it sufficient but with clear room for improvement in transparency.

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%, so the description must compensate. It adds meaningful context by explaining each parameter with examples (e.g., 'amount: Volume to convert (e.g., 1.5)'), clarifying that from_coin and to_coin accept IDs/symbols like 'bitcoin' or 'usd'. This goes beyond the bare schema, though it could specify format constraints or valid values more explicitly.

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 specific action ('convert cryptocurrency using real-time rates') and the resource involved (cryptocurrency/currency pairs). It provides concrete examples (BTC to ETH, USDC to USD) that illustrate the tool's function, making it immediately understandable and distinct from sibling tools like wallet_check or get_transactions.

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 implies usage through examples (e.g., 'BTC to ETH, USDC to USD'), suggesting this tool is for currency conversion, but it doesn't explicitly state when to use it versus alternatives like wallet_check or get_transactions. There's no guidance on prerequisites, limitations, or specific contexts where this tool is preferred over others.

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