get_asset_performance

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

Annotations already declare readOnlyHint=true and destructiveHint=false. Description adds value by specifying return fields (field_type, primary_status, content), noting the inclusion of summaries, and disclosing that per-asset performance labels are unavailable for PMax assets. No contradiction with annotations.

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?

Description is concise with three well-structured paragraphs. Purpose and return fields are front-loaded. No unnecessary words or repetition. Efficient use of space.

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 (two optional params, output schema exists, read-only), the description is mostly complete. It covers purpose, return fields, limitations, and alternative tool. The only gap is the lack of explanation for the customer_id parameter, which is typical in Google Ads tools.

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 coverage is 0% (no parameter descriptions in schema). Description only explains campaign_id as an optional filter to a single PMax campaign, but does not mention customer_id at all. Partial compensation for missing schema descriptions.

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 it gets per-asset details for PMax campaigns (specific verb+resource+scope). It explicitly differentiates from sibling get_detailed_asset_performance by noting the limitation on performance labels and pointing to the sibling for proxy quality data.

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?

Description specifies when to use (to retrieve asset details for PMax campaigns) and explicitly advises against using it for performance labels (BEST/GOOD/LOW), suggesting an alternative tool (get_detailed_asset_performance) for proxy quality assessment.

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