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

No annotations are provided, so the description carries the full burden. It does not state that this is a read-only aggregate query, what permissions or API keys are needed, whether there are rate limits, what the response shape is, or what happens when 'by' is omitted or invalid. Only the aggregation framing is inferable from the single sentence.

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?

A single front-loaded sentence with zero filler; the aggregation semantics and the allowed grouping dimensions arrive first. Nothing is repeated from the schema and nothing needs trimming.

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 six-parameter aggregation tool with no annotations and no output schema, the definition stops short of explaining the default behavior (e.g., whether 'by' is effectively required, what the default result size is, or what fields come back). The complete schema coverage compensates partially, but an agent still lacks enough to know how the grouped result will be shaped.

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 coverage is 100%, so the baseline is 3, but the description genuinely adds value by enumerating the valid values for 'by' (awarding_agency, awarding_subagency, recipient, naics, psc, cfda, state_territory, country) while the schema only says 'grouping'. It does not clarify how the filters (naics, agency, date range) interact with the grouping, which keeps it from a 5.

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 names a specific verb+resource combination: 'Federal spending totals grouped by...' — clearly an aggregation tool, distinct from row-level siblings like federal_awards or federal_award. What it lacks is any explicit differentiation from federal_recipients or company_federal_awards, which an agent could plausibly confuse it with.

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?

There is no guidance on when to use this tool versus federal_awards (raw awards) or federal_recipients (recipient listing), and no mention of prerequisites or exclusions. The agent must infer the aggregation-vs-raw distinction from the word 'totals' alone.

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