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

Annotations declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint=false, establishing the safety profile. The description adds useful context by specifying the aggregation behavior ('across all retailers') and the summary metrics (min/max/avg), going beyond what annotations alone convey.

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 a single, focused sentence that gets straight to the point, stating the operation and key details without any redundancy. It is concise and front-loaded, earning 5.

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 tool's simplicity (one parameter, no output schema), the description sufficiently covers the return value (min/max/avg prices) and scope (across all retailers). It does not explain the response shape or handling of missing products, but for a simple read-only summary, it is nearly complete.

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 schema covers productId with a description ('Product UUID') and full schema coverage (100%). The description adds that the summary is 'for a product', which aligns with the parameter but does not provide additional semantic detail beyond the schema. Baseline of 3 is appropriate.

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 function: 'Get price summary for a product: min/max/avg prices across all retailers.' It identifies the resource (product), the action (get summary), and specific output metrics (min/max/avg), distinguishing it from sibling tools like price history or deal analysis.

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 a use case (getting an aggregated price overview) but does not explicitly state when to use this tool versus alternatives like cf_price_history or cf_list_offers. No exclusions or alternative references are given, so guidance is only implied.

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