usa_spending_over_time

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

Annotations already declare readOnlyHint: true, covering the read-only safety profile. The description adds that data is aggregated by time period, which aligns with the name and schema, but does not disclose additional behavioral aspects such as default date ranges, output format, or pagination.

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 a single, front-loaded sentence with no filler. It clearly states the core action and purpose, making it easy to scan and quickly understand the tool's intent.

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?

The description is brief (16 words) and conveys the primary time-series aggregation and trend use case, but it omits details about optional filters (state, agency, keyword, award type) and output characteristics. The comprehensive schema compensates for these gaps, but the description alone is minimally sufficient for a 7-parameter tool.

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?

The input schema has 100% description coverage for all 7 parameters, including enum values for 'group' and 'award_type'. The tool description itself adds no further parameter-level detail beyond what the schema already provides, so it meets the baseline for high schema coverage.

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 uses a specific verb 'Get' and clearly states the resource: federal spending aggregated by time period (monthly, quarterly, or fiscal year). This distinguishes it from sibling tools like usa_spending_by_agency or usa_spending_by_state, which aggregate by other dimensions.

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 phrase 'Useful for identifying trends' provides a clear context for when to use the tool. However, it does not explicitly mention alternatives or when not to use it, leaving some ambiguity among the related spending tools.

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