List ads

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

The annotations already declare readOnlyHint=true and destructiveHint=false, so the read-only behavior is known. The description adds value by detailing what fields are returned, especially the special handling for responsive search ads with headlines, descriptions, and pinning. This goes beyond what structured annotations 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 a single, dense sentence that front-loads the core purpose and immediately lists useful output details. Every clause contributes meaningful information 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?

For a read-only list tool with no output schema, the description covers the main return fields and available filters, which is largely sufficient. The main gap is the undocumented include_removed parameter, but the overall context is strong enough for an agent to understand and invoke the tool correctly.

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 only 40%, and the description only partially compensates by clarifying that campaign_id and ad_group_id act as filters. It does not explain include_removed, which is a non-obvious boolean parameter, and it adds minimal semantic value beyond the schema's own descriptions for limit and customer_id.

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 uses a specific verb ('List') and identifies the exact resource ('ads'), while also enumerating the returned data (type, status, policy approval, ad strength, final URLs, and responsive search ad assets). This clearly separates it from sibling tools like list_campaigns and list_ad_groups.

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 states that filtering by campaign or ad group is possible, which gives some usage context. However, it does not explicitly explain when to choose this tool over alternatives such as gaql_search or other list tools, nor does it provide any exclusion criteria.

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