Federal Reserve Economic Data (FRED) 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 mentions data retrieval and transformation capabilities but lacks critical details such as rate limits, authentication requirements, error handling, pagination behavior (implied by limit/offset but not explained), or what the output looks like (no output schema). This is inadequate for a tool with 11 parameters and no annotation support.

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, efficient sentence that front-loads the core purpose ('Retrieve data for any FRED series by its ID') and adds supporting features. There's no wasted text, though it could be slightly more structured by separating core functionality from optional features.

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 (11 parameters, no annotations, no output schema), the description is incomplete. It doesn't explain the output format, error conditions, or behavioral traits like rate limits or side effects. While the schema covers parameters well, the description fails to compensate for the lack of annotations and output schema, leaving significant gaps for the 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 description adds minimal value beyond the input schema, which has 100% coverage with detailed parameter descriptions. It mentions 'data transformations, frequency changes, and date ranges,' which loosely maps to parameters like units, frequency, and observation dates, but doesn't provide additional syntax, examples, or constraints. The baseline of 3 is appropriate given the schema does the heavy lifting.

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 verb ('Retrieve') and resource ('data for any FRED series by its ID'), making the purpose evident. However, it doesn't explicitly distinguish this tool from its siblings (fred_browse, fred_search), which would require mentioning that this is for retrieving specific series data rather than browsing categories or searching for series.

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 mentions 'Supports data transformations, frequency changes, and date ranges,' which implies some usage context but doesn't provide explicit guidance on when to use this tool versus fred_browse or fred_search. No alternatives, prerequisites, or exclusions are stated, leaving the agent without clear decision criteria.

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