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

Annotations already cover read-only, open-world, idempotent, and non-destructive behavior. The description adds 'Keyless' (no authentication) and clarifies that a single call returns aggregation rollups, which goes beyond the structured annotations without contradicting them.

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 two sentences with practical examples, front-loading the core aggregation behavior. Every phrase earns its place, with no filler or redundant repetition of schema 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?

Given 7 parameters, no output schema, and strong annotations, the description covers primary use cases and key filters. It lacks explicit return shape (though 'rollups' and 'top N' imply grouped totals) and filter interaction rules, but is sufficiently complete for typical market-sizing queries.

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 only 43%, so the description compensates by mapping category to NAICS/PSC/recipient/awarding agency and mentioning filter options (keywords, NAICS, agency). It adds meaning to parameters that lack schema descriptions, though it does not specify filter combination logic.

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 aggregates federal contract spending by NAICS, PSC, recipient, or awarding agency over a date range. It distinguishes itself from siblings like search_awards by framing it as 'market sizing in one call' with concrete examples.

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 tool provides clear context for when to use it, such as 'top contractors in NAICS 541512 last year' and 'which agencies buy the most cybersecurity', indicating market-sizing scenarios. However, it does not explicitly name alternatives or state when not to use this tool versus search_awards.

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