US Government Open Data MCP

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

Annotations provide readOnlyHint=true, indicating a safe read operation. The description adds valuable behavioral context beyond annotations: it specifies the temporal scope ('Monthly data going back to 1947 for some series'), data granularity ('monthly'), and the breadth of indicators. It does not contradict annotations, as 'Get' aligns with read-only behavior.

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 efficiently structured: it starts with the core purpose, uses bullet points to list key indicators for quick scanning, and ends with temporal context. Every sentence and bullet point adds value without redundancy, making it easy to parse while being information-dense.

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 (retrieving diverse transportation statistics), the description provides strong contextual completeness: it outlines the data scope, temporal range, and indicator types. With annotations covering safety (read-only) and schema fully documenting parameters, the main gap is the lack of an output schema, but the description compensates by detailing what data to expect.

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%, with clear documentation for start_date, end_date, and limit parameters. The description does not add any parameter-specific semantics beyond what the schema provides (e.g., it doesn't explain date formats or limit implications). Baseline score of 3 is appropriate since the schema fully documents parameters.

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 explicitly states the tool's purpose: 'Get Monthly Transportation Statistics' (specific verb+resource). It provides comprehensive detail about the scope ('50+ national indicators including...') and distinguishes itself from sibling tools like 'bts_border_crossings' by covering a broader range of transportation metrics beyond just border data.

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 implies usage context by listing the types of indicators available (e.g., airline traffic, transit ridership), suggesting it should be used for retrieving aggregated transportation statistics. However, it does not explicitly state when to use this tool versus alternatives like 'bts_border_crossings' or other data sources, nor does it mention any prerequisites or exclusions.

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