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

Annotations already establish readOnlyHint and openWorldHint, and the description adds meaningful behavioral context beyond those: it never gives a trust verdict, presents dated signals, and lets the user decide. This directly shapes agent behavior and prevents overclaiming.

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 with no filler. The first sentence front-loads the full list of signals, and the second adds a critical behavioral constraint. 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?

For a simple one-parameter read-only tool, the description covers what the tool returns and how it should behave. It lacks explicit output formatting details, but the description's instruction to 'present the signals and let the person decide' is sufficient given the tool's simplicity.

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% and the only parameter, name, is already documented as 'Nombre, dominio o URL de la tienda.' The description does not add parameter-level details, but the schema carries the full burden adequately, so the baseline score applies.

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 resource (an online store selling in Uruguay or for purchases abroad) and the output (dated trust signals such as domain age, ratings, HTTPS, contact info, return policy, and payment methods). It is not a tautology and is unambiguous, but it does not explicitly differentiate itself from sibling tools.

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 intended use is implied: the tool should be used when someone wants dated signals about an online store's trustworthiness. However, it does not mention when to use alternatives or explicitly exclude other tools, leaving the routing decision to inference.

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