Get vehicle status

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

Annotations already declare readOnlyHint and openWorldHint, so safety is covered. The description adds genuinely useful non-structured behavior: this returns cached last-reported data and will not wake the vehicle, which matters for battery drain and latency. It does not mention data staleness or freshness bounds, which would complete the picture.

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?

Two sentences, front-loaded with the core action and the key behavioral caveat. The long field enumeration is somewhat redundant given an output schema exists, but it still serves as a quick scope preview.

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?

With an output schema covering return values and 100% schema coverage on the sole parameter, the description needs only to explain scope and behavior — which it does. The only gap is guidance on how stale 'last reported' data may be and when to escalate to a refresh.

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% and the single 'vehicle' parameter is fully documented in-schema, including the 'optional if one vehicle' rule. The description adds nothing about the parameter, which is fine given the schema does the work — 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?

States a specific verb and resource ('Get the car's last reported state') and enumerates the domains covered, so the agent knows exactly what comes back. The phrase 'last reported state' implicitly separates it from refresh_vehicle_status, which is the sibling that would fetch fresh 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?

'Does not wake the car' establishes the key selection criterion against refresh_vehicle_status (the non-waking, cached read). It stops short of naming that sibling explicitly, so the routing requires one small inference rather than being stated outright.

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