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

Adds substantial context the annotations cannot convey: per-call cost, the x402/USDC payment flow, the challenge-retry handshake via _meta["x402/payment"], and an HTTP equivalent endpoint. It does not describe result format or limits, but the payment behavior is exactly the kind of operational detail that earns credit here.

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?

Purpose is front-loaded in the first sentence, with payment mechanics and transport fallback following. Three compact sentences, none redundant.

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 6-param optional search with a fully documented schema, the description covers purpose, cost, and invocation path. Only the return shape and result limits are undocumented, and there is no output schema to compensate, which keeps this below a 5.

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% with per-parameter descriptions (including enum-like values for source and class), so the schema carries the parameter burden. The description's only addition is that all params are optional frees ('or use filters alone'), which is consistent but minimal.

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 ('Search') and resource ('FDA, CPSC, and NHTSA recall records'), plus the key differentiator 'in one call' that signals cross-agency aggregation versus the single-source siblings recalls_product_check and recalls_vehicle.

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?

There is no guidance on when to reach for this tool versus recalls_product_check, recalls_recall, recalls_vehicle, or recalls_watch, nor any prerequisites beyond the payment mechanic. The agent must infer that this is the free-text multi-source search sibling from the resource string alone.

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