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

Annotations declare readOnlyHint=false and destructiveHint=false. The description adds context about business permissions, the need for an access check, and handling of grace periods and resubscribe links. It does not detail side effects like ad spending or campaign creation outcomes, but the pre-access guidance is valuable.

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 concise, front-loading the purpose and then delivering critical usage instructions. Each sentence adds value, though it could be slightly streamlined.

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 complexity (6 parameters, no output schema), the description fails to explain parameter semantics or return values. It covers important preconditions but leaves the agent guessing about input meaning and output format.

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?

The schema lists 6 parameters with no descriptions (0% coverage), and the tool description does not explain any parameter or its purpose. Without added meaning, the agent cannot correctly map inputs to needed fields.

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 generates a Magic Audience campaign with ads from product or asset context. However, similar sibling tools like 'create_magic_audience_campaign' and 'create_magic_audience_ad' exist, and the description does not explicitly differentiate this combined action.

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 guidance: check business permissions, note that FREE businesses cannot use it, call check_business_tool_access first, show warnings, and never proceed when access is blocked. This sets clear preconditions but does not offer alternatives or when not to use beyond business tier restrictions.

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