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

Annotations already declare destructiveHint=true, idempotentHint=false and openWorldHint=true, so the risk profile is known. The description adds genuinely useful behavior beyond that: the remote-start window is ~2 minutes, the frunk cannot be closed remotely, and closing the trunk requires a power liftgate. However it says nothing about what happens on failure (disabled feature, unreachable car) or what the call returns.

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?

Front-loaded with the action set, then preconditions, then the safety instruction in the order an agent would need them. Dense but nearly every clause carries a distinct constraint; the opening list is slightly long given the enum already repeats those names.

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 destructive, non-idempotent actuation tool with no output schema, this covers capability, preconditions, safety and time limits well. The remaining gaps are the unexplained 'vin' parameter and no hint about response or error shape when the command is rejected or the car is offline.

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 must carry the parameter burden. It does well for 'command', explaining each enum member's real-world semantics and constraints. It never mentions the 'vin' parameter at all, leaving one of two parameters entirely undocumented.

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 ('send a sensitive command') and enumerates the exact operations: unlock, trunk open/close, frunk open, remote start. An agent can tell this is the immediate-action command tool. It does not explicitly differentiate from the sibling 'car_command', leaving the boundary between the two implied rather than stated.

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?

Gives a clear timing condition ('Use only when the user clearly asks for it now') and a prerequisite ('only works if the owner turned these on during setup or on their Account page'), plus a safety preamble requirement before trunk/frunk opening. It stops short of naming an alternative sibling tool for deferred or queued commands.

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