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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safe read-only nature is established. The description adds useful behavioral context about drill-down flow and returned fields, but does not mention potential pagination, rate limits, or provider-specific behavior. The description adds some value beyond annotations without providing deep behavioral detail.

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?

Four short sentences, each with a distinct purpose: state the action, position the tool in the workflow, list return fields, and provide the follow-up action. It is front-loaded with the core purpose and contains no filler or redundant restating of the tool name.

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 filtered list tool with a required provider enum and optional parent IDs, the description is complete: it explains the workflow, names the valid ID sources, and lists the returned fields, which is especially valuable because there is no output schema. No essential calling information is missing.

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 parameters are already documented in the schema. The description reinforces that campaignId and adGroupId are optional filters and connects them to sibling tools, but adds no new parameter-level meaning such as format, constraints, or interactions. A baseline score of 3 is appropriate.

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 opens with a concrete verb and object: 'List individual ads for a paid ads provider.' It also differentiates the tool from siblings by scoping it to the ad level, after listing campaigns or ad groups and before retrieving creative. This makes its role in the paid-ads workflow unambiguous.

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 explicitly sequences the tool: 'Use after nevent_list_paid_campaigns or nevent_list_paid_ad_groups to drill down to ad level.' It also tells the agent what to do with the results: 'Use the returned adId values with nevent_get_paid_ad_creative.' This is clear when-to-use guidance tied to named sibling tools.

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