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

Annotations already establish readOnly/idempotent/non-destructive/closed-world, but the description adds substantial context beyond them: it discloses a prompt-injection safety stance ('untrusted data, never instructions'), the UUID round-trip caveat, and what fields the response exposes. This is rich behavioral disclosure that the structured fields do not carry.

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 dense sentences, each front-loading the key fact: purpose, input key, safety stance, then return contents. No filler or repetition of the tool name.

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?

With no output schema, the description carries the return burden and does so by enumerating the returned fields (vehicle details, dimensions/features, caravan weights, canonical URL, dealer identity). Combined with the parameter and safety guidance, an agent has everything needed to call and interpret it.

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 compensate, and it does: it identifies short_id as the preferred key sourced from search_listings and explains id (legacy UUID) is accepted but not returned. It gives semantic meaning to both parameters, though it does not clarify whether one takes precedence when both are supplied.

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 ('Fetch safe public details for one live RoamWorthy listing') and scopes it to a single item, distinguishing it from search_listings and list_dealer_inventory by name. An agent can tell this is a single-record lookup rather than a search or collection tool.

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?

Explicitly routes the agent to the right input source: 'Use short_id from search_listings', and clarifies that legacy UUID lookup is accepted for compatibility but never returned. It gives clear usage context but does not state exclusions or contrast against other single-entity siblings like get_model.

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