get_params_by_vin

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

With no annotations, the description carries the full burden. It discloses paid nature, prerequisite (listing history), required credential, and error behavior. It doesn't discuss idempotency or rate limits, but still provides substantial behavioral context beyond a bare 'decodes VIN'.

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?

The description is extremely concise: a one-line header, two bulleted sentences, and no wasted words. Critical information (paid, prerequisite, error) is 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 the output schema exists, return values are covered. The description covers prerequisites, paid status, and error handling. It could mention data freshness or pagination, but for a single-input decode tool, it is adequately complete.

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 the 'omni_id' parameter described as 'VIN, plate number, or advert id'. The description adds that the parameter is used to decode into car-parameter chips, reinforcing its purpose beyond the schema alone.

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 specific verbs ('decode') and resources ('VIN / plate / advert id into car-parameter chips') and lists the decoded attributes, clearly distinguishing from siblings which are general listing or search tools.

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 tool is paid, requires AUTORIA_USER_ID, only works for cars ever listed on AUTO.RIA, and that unresolvable IDs cause tool errors. It does not name alternatives, but the constraints are clear enough to guide use.

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