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

No annotations exist, so the description carries the full burden, and it clearly discloses the non-obvious payment workflow: $0.1 USDC on Base, free to call, and a returned x402 URL that triggers 402 → PAYMENT-SIGNATURE → delivery. It also clarifies the data is a live federal FMCSA record with plain risk flags, which is valuable behavioral context beyond just 'check authority'.

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?

Three dense sentences: what the tool is, what data it returns, who should use it, and how payment works. No filler or duplication of the schema, and critical behavioral details like the x402 URL are front-loaded.

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 no output schema, the description gives enough output expectations (record fields plus risk flags) and explains the unusual x402 retrieval/payment flow instead of assuming inline data. It could be more explicit at tool level about requiring at last one of mc/dot, but the parameter descriptions already state that constraint.

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 schema already documents mc and dot, including MC/docket vs USDOT semantics and the this-or-dot required note. The description adds no additional parameter constraints, formats, or examples beyond what the schema provides, so it earns the baseline 3.

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 uses a specific verb+resource: checking the live federal FMCSA record for a US motor carrier by MC or DOT, and lists concrete fields (operating status, safety rating, fleet size, crash/inspection summary). It also frames the tool around freight-broker/dispatch pre-tender checks, distinguishing it from broker-authority and general vetting siblings.

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?

Explicitly states the use case: the check a freight-broker or dispatch agent runs before tendering a load. It does not name when-not-to-use alternatives like check_broker_authority or check_carrier_basics, so it stops 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.