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

With no annotations, the description does real work: 'prepare (unsigned)' discloses that nothing is signed or sent, '(approve first)' reveals the required follow-up step, and 'Extending adds days' explains cumulative extension behavior. It stops short of describing the returned transaction object or what state the vehicle enters, which leaves a modest gap for a mutation tool.

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?

A single dense sentence, front-loaded with the 'Garage: prepare' verb-resource pair, and every clause (unsigned, duration, approve-first, theft benefit, extension) contributes information without padding.

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 prepare tool with no output schema and no annotations, the description covers purpose, prerequisite, duration bounds, and the effect of extending. The main missing element is what the tool actually returns (an unsigned transaction payload); 'prepare (unsigned)' gestures at it but doesn't spell it out.

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%, so all three parameters are already documented (days '1 to 30', wallet purpose, vehicle token). The description paraphrases the day-range constraint and implies the vehicle must be one you hold, adding marginal meaning beyond the schema — baseline 3 is appropriate.

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 ('prepare (unsigned) parking a vehicle'), with scope (1 to 30 days) and the resulting benefit ('a parked vehicle is harder to steal'). It's clearly distinguishable from neighbors like prepare_vehicle_buy or prepare_vehicle_heist_launch by the parking/garage resource, though it never names a sibling explicitly to reinforce that.

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 parenthetical '(approve first)' supplies the key prerequisite that this is a two-step prepare-then-approve flow, and 'a vehicle you hold' implies eligibility. But it doesn't say when to choose this vs other garage or vehicle actions, so usage is only implied.

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