usa_spending_by_agency

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds the behavioral context that results are aggregated by agency and ranked by spending amount, which is useful. However, it does not disclose details like whether the data is limited to a default fiscal year, how the 'limit' parameter affects ranking, or whether the keyword filter applies to agency names or spending categories. With annotations covering safety, a 3 is appropriate.

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?

Two sentences with no wasted words. The core function is front-loaded, and the second sentence clarifies the output's interpretation. It is appropriately sized for a simple aggregation tool, though it could have used the space to add usage guidance or parameter interaction details.

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?

For a read-only aggregation tool with no output schema, the description is adequate but not complete. It explains what the tool returns at a high level, but an agent would benefit from knowing the default fiscal year behavior, whether results are sorted descending by spending, and how the optional filters (state, keyword, award_type) affect the aggregation. The annotations cover safety, but the lack of output schema and parameter interaction details leaves some gaps.

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%, so the schema already documents all five parameters. The description adds no additional meaning beyond what the schema provides, such as how parameters interact (e.g., whether state and keyword are combined with AND or OR, or how award_type affects the aggregation). Baseline 3 is correct 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 states a specific verb ('Get') and resource ('total federal spending broken down by awarding agency'), and clarifies the output's meaning ('Shows which agencies are spending the most'). It is clear on its own, though it does not explicitly distinguish itself from the sibling tools like usa_spending_by_award or usa_spending_by_state. The name itself is fairly descriptive, and the description adds enough to understand the tool's core function.

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 for agency-level spending analysis but provides no explicit guidance on when to choose this tool over alternatives such as usa_spending_by_award, usa_spending_by_state, or usa_spending_by_recipient. The context signals show many sibling tools in the same domain, so the lack of explicit routing or exclusions leaves the agent to infer the appropriate use case.

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