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

Annotations indicate the tool is not read-only and open-world; the description adds that actual payment occurs on the merchant page, explains the return structure (buy_url, affiliate disclosure), and gives special guidance for used items. This provides useful behavioral context beyond annotations.

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 well-structured with separate sections for purpose, usage condition, return value, and additional notes. It is concise and front-loaded with the primary action, though slightly dense due to multiple 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?

Given the output schema is implied and annotations provide some hints, the description covers the main concerns: when to use, what is returned, and a special case (used items). However, it lacks error handling or prerequisites like having a selected product, and the demo nature is noted only in the title.

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 has two parameters (product_id, quantity) with 0% description coverage. The description does not explain these parameters or their defaults; it only implies product_id contextually. Quantity is not mentioned, leaving agents to infer its meaning from the schema alone.

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 initiates checkout for a selected product in Super Shopping and returns a purchase link, price, and affiliate disclosure. It distinguishes itself from sibling tools (search, compare, recommend) which handle different stages.

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 explicitly says to use the tool when the user shows purchase intent ('이거 살래', '구매하기'), providing clear usage context. It does not mention when not to use or alternatives, but context is sufficient.

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