compare_ad_presence

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

Annotations declare readOnlyHint=true and idempotentHint=true, so the description's safety implications are already covered. The description adds value by specifying the return data (ad counts and format distribution per region), which goes beyond the annotations and helps the agent understand expected output.

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 remarkably concise: a single introductory sentence, a bulleted list of use cases, and a closing sentence about return values. Every sentence adds value, with no redundancy or filler.

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 has 2 required parameters and no output schema, but the description explains the return format (ad counts and format distribution per region). While the exact structure is unspecified, the description provides sufficient context for a simple comparison tool, and annotations (readOnlyHint, idempotentHint) further inform behavior.

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 'advertiserId' and 'regions' are already well-documented in the input schema. The description mentions 'regions' but does not add new semantic details beyond what the schema provides (e.g., maxItems constraint is already present).

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 compares ad presence across multiple geographic regions, with a specific verb ('Compare') and resource ('ad presence'). It lists concrete use cases that distinguish it from sibling tools like get_ad_details or search_advertiser, which are not comparative.

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 explicit 'Use this tool to:' bullet points outlining contexts for use (e.g., competitor activity, market identification). It does not explicitly mention when not to use or alternative tools, but the listed scenarios are clear and differentiated from siblings.

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