Last parked position

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

Annotations already mark this as readOnly and idempotent, but the description adds genuinely new behavioral context: the position only updates when the car parks, so it may lag behind live driving, and it instructs the agent to cite freshness.vehicle_reported_at. This is valuable beyond the structured annotations.

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?

Every sentence earns its place: the first states the result, the second gives the query intent, and the third covers prerequisites and staleness semantics. It is compact, front-loaded, and free of filler.

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 there are no parameters, an output schema exists, and annotations cover the safety profile, the description fully covers what an agent needs: expected data, address caveat, update behavior, and the freshness field to cite. Nothing essential is missing.

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?

The input schema has zero parameters, so there is nothing to document. With no parameters, the baseline is 4, and the description doesn't need to compensate for any missing parameter information.

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 states a specific resource (last parked position) and the exact payload (coordinates, Google Maps link, address). It unambiguously identifies this as the 'where is the car?' tool and is distinct from siblings such as find_car or get_odometer.

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?

The description gives a clear use case: 'Use for: where is the car?' and adds the server prerequisite for address data. It doesn't explicitly name alternative tools or when-not-to-use conditions, but the context is clear enough for an agent to select this tool.

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