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

With no annotations, the description carries the full burden; it usefully discloses that this is a paid, read-only HTTP endpoint ($0.02 via x402) and gives the docs URL, which helps an agent understand cost/auth. It stops short of describing default behavior when no filters are applied, the recency window, or pagination beyond the schema's limit.

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?

It is front-loaded with purpose, then returned fields, then sort/filter behavior, then endpoint metadata. Dense but every clause carries information; the bracketed HTTP/price block is compact and clearly delimited.

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?

There is no output schema, yet the description enumerates the returned record shape (vendor, agency/sub-agency, value, NAICS, start date, place of performance), which is exactly what an agent needs. It omits default query behavior and the relationship to the _changes/_delta siblings, but is otherwise sufficient for calling the 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?

Schema description coverage is only 50% (naics, min_value_usd, and limit are undocumented in the schema), and the description compensates by naming every filterable dimension including NAICS and minimum value. It adds little on syntax, but it closes most of the coverage gap.

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 (federal contract awards from USAspending) and enumerates the returned record fields, so an agent knows exactly what data comes back. It does not, however, distinguish this tool from its near-identical siblings gov_contracts-awards_changes and gov_contracts-awards_delta.

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?

It lists the available filters (vendor, agency, NAICS, minimum value, date) and states records are sorted by value, which implies how to narrow a query, but it never says when to reach for this tool over the _changes or _delta variants. Usage is inferable rather than explicit.

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