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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, covering the safety profile. The description adds context about the impact on P&L accuracy and the returned fields, which is useful but does not reveal additional behavior beyond what annotations and schema provide.

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 concise sentences with no redundancy. The purpose is front-loaded, and the output specification is efficient. 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?

With an output schema present and full schema parameter coverage, the description adequately covers purpose and output. It could mention the read-only nature explicitly, but annotations handle that. The description is complete for a tool of this 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 description coverage is 100%; both parameters (include_zero_cost, stale_older_than_days) have detailed descriptions in the schema. The tool description adds no new parameter semantics, so the 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?

Description clearly states the verb 'Find' and the resource 'products or variants with missing or stale COGS data', and specifies the output (product titles, SKUs, gap reason). It is specific and distinct from siblings like get_cogs_coverage, though it does not explicitly name alternatives.

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 P&L accuracy monitoring but does not explicitly state when to choose this tool over related ones like get_cogs_coverage or get_item_cogs. The parameter schema offers some guidance (e.g., include_zero_cost, stale_older_than_days), but the description itself lacks clear when-to-use or exclusions.

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