US Government Open Data MCP

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 adequately indicates this is a read operation ('Get') and specifies the required input parameter. However, it doesn't mention important behavioral aspects like rate limits, authentication requirements, error conditions, or what happens when an invalid candidate_id is provided. The description doesn't contradict any annotations since none exist.

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 perfectly concise with two sentences that each earn their place: the first states the purpose and output, the second provides critical usage guidance. There's zero wasted language, and the most important information (what the tool does and the prerequisite) is front-loaded.

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 (2 parameters, no output schema, no annotations), the description is adequate but has gaps. It explains the purpose and prerequisite well, but doesn't describe the return format (what the financial summary looks like), error handling, or behavioral constraints. For a financial data tool with no output schema, more detail about the response structure would be helpful.

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?

With 100% schema description coverage, the baseline is 3. The description adds value by explaining the purpose of candidate_id ('Requires a candidate_id') and providing context about how to obtain it ('use fec_search_candidates to find one'), which goes beyond the schema's technical description. However, it doesn't provide similar contextual guidance for the optional 'cycle' parameter.

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 ('Get financial summary') and resource ('for a candidate'), listing the exact financial metrics returned (total raised, spent, cash on hand, debt). It distinguishes itself from sibling tools like 'fec_search_candidates' by focusing on financial data retrieval rather than candidate search, with no tautology present.

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 explicitly provides when-to-use guidance by stating 'Requires a candidate_id (use fec_search_candidates to find one)', naming the specific alternative tool to use first. This creates a clear workflow dependency and distinguishes it from other FEC tools like 'fec_committee_financials' or 'fec_top_candidates'.

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