get_instant_offer

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

No annotations are provided, so the description carries the full burden. It discloses the tool is a read-only operation ('Get'), returns an 'estimated offer range and next steps', and requires certain inputs. However, it does not explain potential side effects, whether actual offers are binding, or the role of zip/mileage. This is adequate but not rich.

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, front-loaded with the core purpose, then input requirements, then output. Every sentence adds value, with no unnecessary words or repetition of schema details.

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 5 parameters, no annotations, and no output schema, the description could do more. It explains the VIN/license plate requirement but leaves ambiguity: the schema marks all params as optional, yet the description implies mandatory inputs. It also doesn't describe the role of zip/mileage, though these are in the schema. Overall, reasonably complete but with notable gaps.

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?

The input schema covers all parameters with descriptions, giving a baseline of 3. The description adds meaning by explaining the relationship between VIN and license plate ('VIN or license plate + state'), clarifying the alternative input methods beyond the schema. This adds value to parameter usage context.

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 clearly identifies the tool's purpose with a specific verb and resource: 'Get an instant cash offer from CarMax for selling your car.' It also distinguishes itself from sibling tools like search_inventory and schedule_test_drive by focusing on the selling/offer scenario, not buying or scheduling.

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 provides clear usage guidance: 'Provide VIN or license plate + state' and states what the tool returns. While it doesn't explicitly compare to alternatives, the purpose is distinct, and the prerequisite information is useful. It does not mention when not to use or list alternatives, but the context is clear enough.

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