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

Annotations already declare readOnly/idempotent/non-destructive/closed-world, so the safety profile is covered. The description adds real behavioral context beyond that: it constrains results to the last complete year's obligations, reports a share per vehicle, and explicitly notes that reservation/eligibility is inferred from the vehicle's name — an important caveat about how the data is derived.

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 a single sentence with no filler, but the nested parentheticals ("(and an optional agency)", "(read from its name)") and a list of vehicle types make it hard to parse on first read. Content is front-loaded reasonably but the syntax is denser than necessary.

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, closed-world lookup with no output schema, the description covers the important things an agent needs: what entities come back (vehicles), what the numbers mean (share of last complete year's money), and how eligibility is determined. Nothing essential for correct invocation appears missing.

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%, with both parameters documented including the 6-digit NAICS format and the agency name-or-code convention. The description only restates that naics is 6-digit and agency is optional, adding essentially no semantics beyond the schema, so the baseline 3 is appropriate.

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 resource domain — shared contract vehicles (GWACs, multiple-award IDIQs, GSA Schedule, BPAs) scored against NAICS-coded contract money — which is clearly distinct from siblings like get_catalog, browse_codes, or search_recipients. It reads as a dense fragment rather than a verb+object sentence, but an agent can still tell what it returns.

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?

Usage is only implied through the input condition: you need 6-digit NAICS codes, optionally narrowed by agency. There is no statement of when to prefer this over get_catalog or browse_codes, and no exclusions or prerequisites (e.g. what happens with non-6-digit codes, or coverage limits of the underlying data).

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