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

With no annotations, the description carries the behavioral burden. It discloses what is returned (product families with a from-price) and what is deliberately omitted (billing variants). The search framing implies read-only behavior, though side effects and error cases are not mentioned.

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 Storefront context and the product list are front-loaded. Every phrase adds useful information.

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 description covers what it searches, what it returns, and where to find billing variants. The output shape and limit behavior could be more explicit, but an agent has enough context to select and invoke the tool correctly.

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 description adds meaning to the required query parameter by framing it as a search over three named products. However, the optional limit parameter is undocumented in both the schema and the description, so its semantics are left to inference.

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?

States a specific verb ('search'), a resource ('Coil's three products'), and explicitly lists the product names. It also distinguishes the tool from get_product_details by noting that billing variants come back there.

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?

Names get_product_details as the source for billing variants, giving a clear alternative for that specific case. It does not explicitly contrast with search_policies or say when not to use this tool, so it stops short of a perfect 5.

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