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

The description adds real behavior beyond the annotations: a confirmation gate that may be waived by the owner and a read-only-mode block. It doesn't disclose what happens on a rejected confirm or whether unlocking is reversible, so it stops short of full transparency.

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?

Three short sentences, front-loaded with the action and then the gating conditions. Nothing is wasted and no repetition of the title beyond the necessary verb.

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 mutation tool with annotations and no output schema, the definition covers the critical gate (confirm) and the mode restriction. Only the vin parameter's meaning and failure behavior remain unexplained, which is a modest gap.

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 50%. The description does add conditionality to 'confirm' beyond the schema's terse 'Must be true when confirmations are required,' but the 'vin' parameter is never mentioned in either the schema or the description, leaving its role unstated.

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 opens with a specific verb and resource ('Unlocks the vehicle'), which implicitly contrasts with the sibling lock_vehicle. It doesn't name a sibling or scope explicitly, but the action is unmistakable.

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?

It states the operational preconditions clearly: confirm=true is required unless owner confirmations are disabled, and the call is blocked in read-only mode. It doesn't discuss when to prefer this over siblings, but for a dedicated single-action tool that exclusion is not needed.

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