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

Annotations already mark the operation as non-read-only and non-idempotent, so the side-effecting nature is known. The description adds useful context that the dealership replies directly and usually quickly, and that sharing contact details is an intentional action, but it doesn't detail persistence, downstream effects, or response behavior beyond what the output schema already covers.

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 sentences with no filler. The first sentence states the action and target; the second adds the critical consent gate. Everything included earns its place.

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 submission tool with an output schema and annotations covering side effects, the description plus schema is sufficient for correct invocation. It covers the action, the prerequisite, and the source of dealerId, while the schema fills parameter details. A small gap is the lack of explicit guidance about when a general inquiry vs. a VIN-specific inquiry is appropriate, but the schema already notes that.

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 67%, with dealerId, vin, name, and phone already described. The description adds useful mapping—'buyer's question' maps to message, 'contact details' maps to name/phone/email, and 'the dealership selling the car' clarifies dealerId provenance—but it doesn't add format, optionality, or edge-case guidance beyond the schema.

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 uses a specific verb ('send') and names a clear resource: the buyer's question and contact details to the dealership selling the car. It is readily distinguishable from sibling read/search tools like get_vehicle and list_dealers, though it doesn't explicitly name them.

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 gives an explicit precondition: only call after the buyer has explicitly agreed to share their name and phone number with that dealership. This clearly tells an agent when to call and implies that calling without consent is wrong, though it doesn't discuss alternative tools.

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