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

Annotations already declare readOnly/idempotent/openWorld, and the description adds genuinely new behavioral context: it is a paid tool ($0.02/call, x402 on Base) and returns payment requirements unless payment_signature is supplied. This payment flow disclosure is valuable beyond the annotation set.

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?

Front-loads the [Procurement] tag and the core purpose, then usage, price, payment behavior, and a sample link. Dense but each sentence carries information, with no filler.

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?

No output schema exists, so the description carries return-value burden and does disclose the payment-requirements response when unpaid. For an 8-param, no-required-param search tool this is largely complete, though it could say more about result shape.

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%, so all 8 parameters (days, limit, naics, agency, award_type, etc.) are already documented. The description only loosely references recipient/agency intent and adds no syntax or default detail beyond the schema, so 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?

States a specific verb and resource: find US federal contracts and grants recipients or what a company was awarded. The US federal / USAspending.gov scope clearly distinguishes it from siblings like search_eu_grants and search_tender_awards.

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?

Gives clear usage contexts (competitor research, partner finding, US public-sector sales leads), which tells an agent when it fits. It does not explicitly name an alternative or exclusion, so it stops just short of full routing guidance.

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