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

The annotations already declare readOnlyHint=true and destructiveHint=false, covering the safety profile. The description adds a bit of detail about the content returned (sponsored results permission and brand/ingredient preferences), but does not disclose any further behavioral traits such as permissions, rate limits, or side effects. Since annotations are present, the description is adequate but does not go beyond what the annotations already imply.

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, well-structured sentence that front-loads the core purpose and specifies the data attributes. There is no filler or unnecessary detail, making it highly efficient for an agent to parse quickly.

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?

This is a simple read-only lookup with only two fully documented parameters, and the presence of an output schema means return values are already defined elsewhere. The description covers the essential information—what the tool retrieves—without needing to explain API details. Everything necessary for correct invocation is present.

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 parameters (shopper_id and tenant_id) are fully documented in the schema with clear descriptions. The tool description does not add any additional meaning beyond what the schema provides—it only mentions the data returned, not the parameters themselves. Baseline 3 is appropriate when the schema handles parameter documentation.

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 what the tool does: retrieves a shopper's ad preferences, specifically whether they allow sponsored results and their brand/ingredient preferences. This is a specific verb-resource combination that distinguishes it from siblings like sponsored_search (which likely performs searches rather than reading preferences). However, it does not explicitly name any distinct tool for contrast, so it falls short of a 5.

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 provides no guidance on when to use this tool versus alternatives. It does not mention that it is a read-only preference lookup, nor does it explain when to prefer it over sponsored_search or other siblings. There is no explicit context or exclusion criteria, leaving the agent to infer when this tool is appropriate.

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