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

Discloses that returns are at YMM-granularity, includes NHTSA disclaimer, campaign details, Park It advisories, and notes that a recall may not apply to every VIN. Annotations already indicate read-only, idempotent, non-destructive; description adds valuable behavioral context without contradiction.

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?

Concise and well-structured: first sentence states purpose, next paragraph adds granularity details and usage guidance. No wasted words.

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 the simple one-parameter schema and presence of output schema, the description covers purpose, usage, behavioral nuances, and disclaimers. It is fully adequate for an agent to correctly invoke the tool.

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 clear description. The description does not add significant parameter-specific meaning beyond what the schema provides, 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?

The description clearly states the verb 'Get', the resource 'NHTSA open safety recalls', and the input 'by VIN'. It is specific and distinguishes itself from sibling tools like get_safety_rating which covers different safety data.

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 when to use the tool ('when a shopper asks about recalls, safety campaigns...') and notes it is a required step in specific playbooks. Provides clear context for selection.

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