List line items

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

No annotations are provided, so the description carries the full burden. Beyond 'Supports a filter expression' it says nothing about pagination behavior, default network resolution, permission requirements, or whether results are truncated.

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?

Two short sentences, front-loaded with the verb and resource, with no filler. The second sentence is thin but earns its place by signalling filter support.

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 tool with no annotations and no output schema, the description should at least hint at what is returned (line item fields) and how paging works. As written, an agent cannot tell what a response contains or how to page through results.

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 filter, pageSize, and networkCode are fully documented in the schema itself. The description's single mention of the filter expression adds no syntax or behavior beyond what the schema already states; baseline 3 applies.

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?

States a clear verb+resource (list Ad Manager line items) and adds a purpose clause that ties it to report data. It does not explicitly distinguish itself from list_orders or list_reports, but the resource noun is specific enough for selection.

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?

'for context alongside report data' implies the intended moment of use (enriching report output), which is more than nothing, but there is no explicit when-not or named alternative among list_reports/run_report/list_orders.

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