US Government Open Data MCP

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

Annotations indicate readOnlyHint=true, which the description does not contradict, as 'Get' implies a read operation. However, the description adds minimal behavioral context beyond this, such as not mentioning rate limits, authentication needs, or pagination behavior. With annotations covering the safety profile, the description adds some value (e.g., output format hint) but lacks rich behavioral details, warranting a baseline score.

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 front-loaded, consisting of two sentences that efficiently convey the tool's purpose and differentiation from a sibling. Every sentence earns its place by providing essential information without redundancy, making it easy for an agent to parse quickly.

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 (5 parameters, 3 required) and the presence of annotations (readOnlyHint=true) but no output schema, the description is largely complete. It clarifies the tool's purpose and usage relative to siblings, though it could benefit from more behavioral context (e.g., output format details). However, it adequately supports agent decision-making in this 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?

Schema description coverage is 100%, meaning all parameters are documented in the schema itself. The description does not add any parameter-specific details beyond what the schema provides, such as explaining the 'limit' default or 'sort' options. Given the high schema coverage, the baseline score of 3 is appropriate, as the description does not compensate but also doesn't detract.

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 a specific verb ('Get') and resource ('full list of cosponsors for a bill'), including key details like party affiliation and sponsorship dates. It explicitly distinguishes this tool from its sibling 'congress_bill_details' by noting it returns individual cosponsor details versus a party breakdown summary, ensuring precise differentiation.

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 explicit guidance on when to use this tool versus an alternative by stating 'unlike congress_bill_details which only provides a party breakdown summary.' This directly informs the agent to choose this tool for individual cosponsor details over the sibling's summary, offering clear context for selection.

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