US Government Open Data MCP

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 states the tool is for searching, which implies a read-only operation, but doesn't specify whether it's safe, if it requires authentication, rate limits, or what the output looks like (e.g., list of series IDs or detailed metadata). The examples add some context but don't cover behavioral traits like pagination or error handling, leaving significant gaps.

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 highly concise and well-structured: the first sentence clearly states the purpose, and the second provides relevant examples without unnecessary details. Every sentence earns its place by enhancing understanding, and it's front-loaded with the core functionality, making it efficient for an agent to parse.

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 moderate complexity (a search function with 2 parameters), no annotations, and no output schema, the description is adequate but incomplete. It covers the basic purpose and provides examples, but lacks details on behavioral aspects (e.g., what the search returns, error conditions) and doesn't compensate for the absence of annotations or output schema, leaving the agent with gaps in understanding the full context.

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 'query' documented as 'Keywords' and 'limit' as 'Max results (default 20)'. The description adds minimal value beyond this, as it only reiterates the keyword aspect through examples. Since the schema already does the heavy lifting, the baseline score of 3 is appropriate, as the description doesn't provide additional syntax, format details, or constraints not covered in the schema.

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: 'Search FRED series by keyword.' It specifies the verb ('Search'), resource ('FRED series'), and scope ('by keyword'), making it easy to understand what the tool does. However, it doesn't explicitly differentiate from sibling tools like 'fred_series_data' or 'fred_series_info', which might handle specific series retrieval rather than keyword searching.

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 implied usage through examples ('GDP', 'unemployment', etc.), suggesting it's for finding FRED series based on keywords. However, it lacks explicit guidance on when to use this tool versus alternatives (e.g., 'fred_series_data' for data retrieval or 'bls_search_series' for BLS data), and doesn't mention prerequisites or exclusions, leaving the agent to infer context from the examples alone.

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