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

Annotations already disclose destructiveHint=true and non-idempotence, so the safety bar is lower. The description adds genuinely useful context that a confirmation gate exists, but says nothing about vehicle-awake requirements, latency, or what a partially-open/close state returns, leaving meaningful behavioral gaps.

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 short sentences with the action first and the constraint second; nothing is padded. It is terse to the point that the vin and close-path semantics are omitted.

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 3-parameter physical-actuation tool with no output schema, the description covers the core action and the confirm gate but leaves gaps around targeting (vin), whether closing also requires confirmation, and prerequisites such as waking the vehicle.

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 description coverage is 0%, so the description carries weight. It explains the confirm parameter's gating role (for opening) and implicitly defines which_trunk values (rear/front), but the vin parameter is never mentioned and it does not state whether confirm is required for closing.

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 concrete action and resource: opening/closing the rear trunk or front trunk (frunk), and clarifies the 'frunk' term. It is easily separable from all siblings (lock_vehicle, flash_lights, set_climate), none of which touch the trunk. No explicit sibling differentiation is needed here, so a 4 rather than 5.

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 only usage guidance is a conditional prerequisite: setting confirm=true when confirmations are enabled. There is no statement of when to prefer this over related actions (e.g., unlock_vehicle first, or wake_vehicle prerequisites), so selection context is only implied.

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