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

Annotations already declare readOnlyHint=false, idempotentHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is covered structurally. The description adds essentially nothing beyond that - no mention of whether the vehicle must be awake, whether the change persists, or what happens for an offline vehicle - and largely restates the title.

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 a single front-loaded sentence with zero filler, which is good structurally. However, the brevity is achieved through under-specification rather than efficiency, since key facts about targeting and preconditions are simply absent.

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 two-parameter actuation tool with no output schema, the agent still needs to know how to target a vehicle and what state the vehicle must be in. With 0% schema description coverage and no annotations explaining preconditions, the definition leaves too much to guesswork.

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 the full burden of explaining parameters. "On or off" loosely maps to the required boolean 'on', but the 'vin' parameter, which selects the target vehicle in a multi-vehicle account, is never mentioned, leaving a required-by-practice parameter 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?

The description names a specific resource (Sentry Mode) and a specific verb pair (turns on or off), so an agent can immediately tell what the tool does. It does not need to differentiate from siblings since none of the listed tools touch Sentry Mode, but it also offers no scoping detail beyond the bare toggle.

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?

There is no guidance on when to use this versus alternatives, no preconditions (e.g. vehicle must be awake or online), and no note on effects such as battery drain. The agent must infer all invocation context from the tool name alone.

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