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

With no annotations, the description carries the full burden of behavioral disclosure. It reveals the output (merchant links) and the sources, but does not mention whether any network requests are made, how current the data is, or what happens if a product is unavailable. It is adequate but not deeply transparent.

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 exactly two sentences, front-loaded with the primary purpose and immediately followed by a concrete statement of what the user gets (merchant links). Every word 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?

The tool is simple: two well-described parameters and no output schema, but the description explains the core return value (merchant links) and examples. It could mention country-specific behavior or current availability, but it is sufficiently complete for a straightforward comparison tool.

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 100%, so both 'query' and 'country' already have clear descriptions in the schema. The tool description adds no extra meaning to the parameters, so the baseline score of 3 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 states the tool's verb ('Compare'), resource ('product prices'), and scope ('across multiple sources'). It also names the specific merchants (Idealo, Amazon, Google Shopping), making it distinct from sibling tools like product_search or barcode_lookup.

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 implies usage for price comparison but provides no explicit guidance on when to use this tool versus siblings such as product_search or category_trends. There are no exclusions or alternative recommendations, leaving the agent to infer the appropriate context.

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