check_vehicle

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

With no annotations, the description carries the full burden. It discloses that the lookup is 'best-effort' (implying potential failure), that it points to the official state-transport check, and that the manual URL is always returned for verification. This gives users realistic expectations about reliability and provides a fallback.

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 two sentences with no wasted words. 'Free vehicle trust check' immediately conveys the purpose, and the rest specifies scope and limitations. It is well-structured and front-loaded with key information.

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?

The description lacks explicit details about the return value beyond stating that the manual URL is always returned. It does not specify the structure or content of the automated lookup result, error handling, or what 'trust check' means in terms of output. Since there is no output schema, this is a gap that could affect an agent's ability to interpret the result correctly.

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 the schema already documents both parameters. The description does not add extra meaning beyond noting that the check is free and covers specific aspects. It does not elaborate on parameter usage or constraints beyond what's in the schema, so it meets the baseline for high-coverage schemas.

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 explicitly states the tool's function: a free vehicle trust check that verifies registration validity and written-off status via an official state transport source. It distinguishes itself from paid PPSR by noting encumbrance is out of scope. This is a clear, specific purpose that differentiates it from sibling tools.

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 description implies when to use it: when you need a free, government-sourced registration and written-off check. It explicitly states when not to use it for encumbrance information (paid PPSR only). However, it does not explicitly name an alternative tool or contrast with siblings, but given the sibling list, no other tool seems to perform this function, so it's adequate.

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