Financial Modeling Prep 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 of behavioral disclosure. It mentions 'real-time trading activity' and 'key details such as trade prices, sizes, and timestamps,' but does not cover critical aspects like rate limits, authentication requirements, error handling, or the format of returned data. For a tool with no annotations and no output schema, this leaves significant gaps in understanding how the tool behaves and what to expect from its execution.

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 concise and well-structured, consisting of two sentences that efficiently convey the tool's purpose and key features. It avoids unnecessary details and is front-loaded with the main functionality. However, it could be slightly improved by integrating usage guidelines or behavioral details without sacrificing brevity.

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 of financial data tools and the lack of annotations and output schema, the description is incomplete. It covers the basic purpose but misses essential contextual information such as data format, potential limitations (e.g., availability of aftermarket data), and how results are structured. For a tool that likely returns detailed trade information, more guidance on output expectations is needed to be fully helpful for an AI agent.

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 input schema has 100% description coverage, with the 'symbol' parameter documented as 'Stock symbol.' The description does not add any additional semantic context beyond this, such as examples of valid symbols or formatting requirements. Given the high schema coverage, the baseline score of 3 is appropriate, as the schema adequately handles parameter documentation without extra value from the description.

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: 'Track real-time trading activity occurring after regular market hours' with the FMP Aftermarket Trade API, specifying it accesses 'trade prices, sizes, and timestamps for trades executed during the post-market session.' This is a specific verb ('track') and resource ('aftermarket trade activity'), but it does not explicitly differentiate from sibling tools like 'getAftermarketQuote' or 'getBatchAftermarketTrade,' which likely serve related but distinct purposes.

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 mentions the context of 'after regular market hours' but does not specify prerequisites, exclusions, or compare it to sibling tools such as 'getAftermarketQuote' (which might provide quotes rather than trades) or 'getBatchAftermarketTrade' (which might handle multiple symbols). This lack of comparative guidance limits its utility for an AI agent in selecting the correct tool.

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