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 behavioral context by specifying filtering capabilities and defining hearings, but doesn't disclose other traits like pagination behavior (implied by 'limit' parameter), rate limits, or authentication needs. With annotations covering safety, the description adds some value but not rich behavioral details.

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: two sentences that directly state the tool's function, filtering options, and a brief definition. Every sentence earns its place with no wasted words, 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 (list operation with filtering), rich schema coverage (100%), and annotations (readOnlyHint), the description is mostly complete. It covers purpose and parameters but lacks output format details (no output schema) and doesn't fully address sibling differentiation. For a read-only list tool, this is adequate but not exhaustive.

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 parameter descriptions (e.g., 'Congress number', 'Chamber', 'Max results (default: 20)'). The description mentions filtering by congress and chamber, aligning with the schema but not adding significant semantic value beyond it. The baseline score of 3 is appropriate when the schema does the heavy lifting.

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: 'List congressional hearings' (verb+resource). It specifies filtering capabilities ('Filter by congress and chamber') and provides a brief definition of hearings. However, it doesn't explicitly differentiate from sibling tools (e.g., congress_hearing_details, congress_committee_meetings), which would be needed for a perfect score.

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 mentioning filtering parameters (congress and chamber) and defining hearings. However, it doesn't provide explicit guidance on when to use this tool versus alternatives (e.g., congress_hearing_details for specific hearings, congress_committee_meetings for broader committee events), nor does it mention prerequisites or exclusions.

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