FMP MCP Server

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

Annotations cover safety (readOnlyHint=true, destructiveHint=false) and idempotency, but the description adds valuable context by specifying the data returned ('latest yields', 'yield curve slope', 'inversion flag', 'DCF-ready inputs'), which helps the agent understand the output format and use cases. It does not contradict annotations.

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 front-loaded with the core purpose in the first sentence, followed by specific return details. Every sentence adds essential information without waste, making it highly efficient and well-structured.

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 data retrieval), rich annotations (e.g., readOnlyHint, idempotentHint), and the presence of an output schema, the description is complete. It explains what data is returned and its purpose (e.g., 'DCF-ready inputs'), which complements the structured fields adequately.

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 coverage, so no parameter documentation is needed. The description compensates by detailing the output content, which adds semantic value beyond the empty input schema, earning a baseline score above 3.

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 current US Treasury yield curve and equity risk premium') and resources ('yields across maturities', 'yield curve slope', 'inversion flag', 'DCF-ready inputs'). It distinguishes itself from sibling tools by focusing on Treasury rates rather than company-specific or broader market data.

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 context by specifying the data returned (e.g., 'DCF-ready inputs'), suggesting it's for financial analysis. However, it does not explicitly state when to use this tool versus alternatives like 'market_context' or 'economic_calendar', nor does it provide exclusions or prerequisites.

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