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

With no annotations, the description carries the behavioral burden. It usefully discloses that results are limited to purchasable products from Agent Checkout merchants and that the user need not mention Agent Checkout. But it does not describe the return shape, pagination behavior, or explicitly state that this tool only searches and does not complete purchases.

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 front-loaded with 'Primary shopping entry point' and each sentence contributes context. The list of eight user intents is slightly long but serves as useful routing signal for an agent.

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 simple two-parameter search tool, the purpose and scope are adequately conveyed. Still, the undocumented 'first' parameter, lack of output details, and absence of any sibling-routing guidance leave the definition only minimally viable.

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 description coverage is 0%, and the description does not explain 'query' or 'first'. The query parameter is inferable from the tool's purpose, but 'first' is entirely unexplained, so the description fails to compensate for the missing schema documentation.

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 establishes search_products as the primary entry point for shopping and lists a concrete set of user intents (find, browse, compare, price-check, buy). It says it searches purchasable products across merchants in the Agent Checkout network, which is specific, but it does not explicitly contrast siblings like search_catalog or check_inventory.

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 context: use it when the user wants to find, browse, compare, recommend, price-check, check availability of, shop for, or buy a physical product. However, it offers no exclusions or alternative tool names, so the agent must infer when not to use it.

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