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 effectively describes the aggregation behavior ('Groups by doctor and sums all their payments, sorted by total descending'), which is crucial for understanding the tool's output. However, it lacks details on potential limitations such as data freshness, error handling, or performance characteristics (e.g., response time for large datasets). For a tool with no annotations, this is a moderate but not comprehensive disclosure.

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. It uses three sentences: the first states the core functionality, the second explains the aggregation and sorting logic, and the third provides usage guidance. Every sentence adds value without redundancy, and key information is front-loaded. There is zero waste in the wording.

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 complexity (aggregation and sorting with 5 optional parameters), no annotations, and no output schema, the description does a good job of explaining the core behavior and purpose. However, it lacks details on the output format (e.g., what fields are returned, pagination) and doesn't mention any prerequisites or constraints beyond the parameters. For a tool with no output schema, this is a notable gap, but the description is otherwise complete for basic usage.

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 well-documented in the input schema. The description does not add any parameter-specific semantics beyond what's already in the schema (e.g., it doesn't explain interactions between parameters like how 'state' and 'specialty' combine). Given the high schema coverage, the baseline score of 3 is appropriate as the description doesn't compensate for schema gaps but also doesn't contradict it.

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 specific verbs ('Find', 'aggregates', 'sums', 'sorted') and resources ('HIGHEST-PAID doctors', 'TOTAL payments received'). It explicitly distinguishes this tool from siblings by emphasizing it's 'the key tool for finding doctors with the biggest pharma relationships', which differentiates it from other open_payments tools that focus on different aggregations (e.g., by company, hospital, or specialty).

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 usage guidance by stating 'This is the key tool for finding doctors with the biggest pharma relationships.' This clearly indicates when to use this tool (for identifying top-paid doctors based on aggregated payments) versus alternatives like 'open_payments_by_company' or 'open_payments_by_specialty' which serve different analytical purposes. The guidance is direct and contextually appropriate.

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