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

Annotations already declare readOnlyHint and openWorldHint, but the description adds genuinely non-obvious behavior: per-call pricing ($0.003 USDC via x402 on Base/Solana/Arc), the fact that failed calls are not charged, and that enrichment is drawn from award pages. It stops short of detailing failure modes or rate behavior.

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 dense sentence, but it is front-loaded with source and query mode, then fields, pagination, and pricing. Every clause carries information; minor density cost for how much it packs in.

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?

With an output schema present, return-value detail is not required, and the description covers source, filterable fields, pagination, enrichment, and billing. Complete enough for correct invocation; only explicit sibling routing is absent.

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 adds meaning: it clarifies that details enriches only the top results from award pages (not all rows) and that 10 results are returned per page. This gives the agent context the property descriptions alone don't convey.

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?

States a specific verb (keyword search) and resource (SBIR/STTR small-business R&D awards) with the authoritative source (SBIR.gov/SBA). The program-level specificity implicitly distinguishes it from generic grant siblings like gov_grants_gov, but it never names an alternative explicitly.

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 keyword-search framing and the example keywords in the schema. There is no explicit when-to-use, when-not-to-use, or named sibling alternative (e.g. gov_grants_gov), leaving routing to inference.

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