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

With no annotations, the description carries the full behavioral burden. It usefully discloses that the data is 'synthetic' with per-value provenance, which matters for how an agent should treat the values, but it says nothing about missing-listing behavior, permissions, or failure modes.

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?

Two tight sentences with no filler; the output nature is front-loaded and the ID format follows immediately. Nothing needs trimming.

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 single-parameter read tool with no output schema, the description adequately characterizes both the input form and the returned record's nature, saving the need for an output schema. It omits error/not-found behavior, which is the only notable 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 0%, so the definition must compensate, and it does by specifying that listing_id is either 'dealer_key:VIN' or 'the urn' — concrete format information absent from the schema. It stops short of examples or validation rules, but this is meaningful added semantics for a single required param.

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 the specific resource returned ('Full synthetic listing record with per-value provenance') for the get_listing operation, so the agent knows this is a record-fetch by ID. It does not explicitly contrast itself with siblings like search_inventory or get_dealer, but the resource is unambiguous.

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 tool versus alternatives such as search_inventory (to find listings) or get_dealer (dealer data). The only usage-adjacent information is the accepted ID form, which is parameter detail rather than routing guidance.

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