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

The description goes beyond annotations by explaining that the tool compares verified used options with the best new price, condition, returns, and warranty. It adds behavioral context (e.g., decision-making) that annotations alone do not cover. However, it could mention whether it provides purchase links or external site navigation.

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 concise, with two sentences that front-load the core purpose and provide immediate usage context. No redundant information, every sentence 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?

Given the parameter count, full schema coverage, presence of an output schema, and sibling tools, the description is complete. It explains the tool's decision aspect and when to invoke it, leaving no obvious gaps for an AI agent.

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 the three parameters clearly. The description does not add significant extra meaning to the parameters; it focuses on the tool's overall function. Baseline score of 3 is appropriate.

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 states the tool's purpose: finding where to buy an exact product used/refurbished/open box and deciding if the cheaper alternative is worth it. It lists specific example queries and differentiates from sibling tools like find_best_total_deal, which likely focuses on new products.

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 explicit usage guidance with example requests like 'buy used' or 'is used worth it?'. It implies context but does not explicitly state when not to use the tool or compare it to alternatives, which would make it stronger.

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